A Virtual Tour of Kin Klizhin

Sign at Kin Klizhin

Chaco Culture National Historical Park includes, in addition to the famous archaeological sites in Chaco Canyon itself, four “outlying” great houses located outside the canyon but in close proximity to it and showing considerable evidence of close contact with people there and integration into the system centered on the canyon.  One of these is Kin Klizhin (Navajo for “black house”), which lies just west of the main canyon on a small tributary of the Chaco River known as Kin Klizhin Wash.  The land surrounding Kin Klizhin was originally a detached unit of the park like the land surrounding the other in-park outliers, but over time the park boundaries have been expanded to connect it to the main unit.  This can be seen clearly on the official park map.  Also evident on the map, however, is that Kin Klizhin is not accessible directly from within the main park unit, and it is necessary to leave the park to get to the road that leads to it.

Sign on Road to Kin Klizhin

The road to Kin Klizhin is a small two-track dirt road that branches off from New Mexico 57, the south road out of the park heading toward Seven Lakes and Crownpoint.  There isn’t a sign right at the junction, but there is a small one a short distance afterward, and there aren’t a whole lot of other roads around there so it’s hard to miss.  The junction comes at the point where 57 curves from going east-west along the San Juan-McKinley county line to going south toward Seven Lakes.

Road to Kin Klizhin

The road to Kin Klizhin is considerably more basic than 57 (which is to say that if you think 57 is the worst road you’ve ever seen, you probably shouldn’t try to go to Kin Klizhin), but it’s generally passable with any sort of vehicle.  After the summer rains it may become washed out in places, so a high-clearance vehicle would be preferable.  Four-wheel drive isn’t really necessary except maybe if it’s actively raining, in which case you probably shouldn’t be trying to do this trip at all.  The road goes over some fairly hilly terrain for a few miles before reaching Kin Klizhin, which is right on the edge of the park boundary.

Kin Klizhin

Kin Klizhin is completely unexcavated, and it isn’t very large as Chacoan great houses go, but it’s one of the better-preserved and more impressive ones.  This is due largely to its tower kiva, which is still in fairly good shape (although a look at the historic photographs at the Chaco Archive shows that it has deteriorated quite a bit in the past century).  Tower kivas are among the more mysterious aspects of the Chacoan system.  The term often gets thrown around a bit loosely, but it is generally used to refer to round rooms that have multiple levels with floors between them.  This is in contrast to the “elevated” or “blocked-in” kivas built into the roomblocks at many great houses both inside and outside the canyon; although those can in some instances be more than one story in height, they always have only one floor.

Interior of Tower Kiva at Kin Klizhin

Tower kivas, which are found mostly at outlying great houses, usually  have two or three levels remaining.  Some have argued that they all originally had four levels, symbolizing the four worlds through which the people passed in some Pueblo origin legends, but this is a rather extreme jump to conclusions given that we don’t actually have any idea what these tower kivas were for.  There’s nothing like them in modern Pueblos.

Hosta Butte Framed by Kin Klizhin

Some have argued that the tower kivas were part of a signaling network using line-of-sight relationships between great houses.  A fair amount of data on the line-of-sight relationships has been assembled, but the role of the tower kivas in it is doubtful, and some research by John Kantner has recently suggested that at least in the southern San Juan Basin (where tower kivas are pretty common) they probably didn’t serve as part of a signaling network.  Whatever they were for, tower kivas are certainly impressive, and the one at Kin Klizhin is a good example.  It has collapsed enough that the main parts still standing are the corners, but they are still standing quite high, and from certain angles they look like football goalposts.

"Goalposts" at Kin Klizhin

The function of the outliers in general, not just those with tower kivas, is a matter of intense debate and little consensus.  “Inner-ring” outliers like Kin Klizhin are particularly odd.  Were they examples of Chacoan colonization out from the canyon into the surrounding area?  If so, why were the Chacoans moving out?  If not, who was building them, and why?

Earthen Dam near Kin Klizhin

These aren’t really answerable questions given current information, but a few possibilities have been suggested.  Kin Klizhin lies in a relatively promising area for floodwater agriculture, in a valley near the canyon with a wash that could be easily dammed to provide a reservoir for water storage.  There is in fact an earthen dam near the great house, although it’s impossible to tell if it’s actually ancient rather than a modern Navajo construction.  (It could also be both; Navajos have been known to use and modify Anasazi dams in many areas.)  One intriguing thing about the area around Kin Klizhin is that despite its agricultural potential it seems to have relatively few small-house sites compared to other outlier communities, which suggests a small population that could have easily produced an agricultural surplus for export to Chaco.

Rim Sherd at Kin Klizhin

Like the other outliers, Kin Klizhin gets many fewer visitors than the main sites in the canyon.  This makes it a very peaceful, quiet place to visit.  There are a lot of potsherds and other artifacts lying around near the great house, since fewer people come around and steal them.  A visit to Kin Klizhin isn’t for everyone, and it’s particularly not for the many people who come into the Chaco visitor center furious about the lack of paved roads, but for the adventurous few who are willing to take the effort to get there it’s definitely worth a visit.

Heavily Reduced Walls at Kin Klizhin

And, of course, there are some other interesting ideas out there about Kin Klizhin and its role in the Chaco system, but discussion of them will have to wait for another day.

Tower Kiva Bench at Kin Klizhin

Advertisement

Read Full Post »

A Virtual Tour of Una Vida

Una Vida Sign

One of the questions we get most often at Chaco from visitors who have just arrived is whether it’s a walking or a driving thing.  It’s both, really.  For most of the sites, especially the really impressive ones, you drive a few miles from the Visitor Center then walk a few hundred yards and do a self-guided tour (or, if there is one available, a guided tour).  This is how it works for Pueblo Bonito, Chetro Ketl, Pueblo del Arroyo, and the other sites in the “Downtown Chaco” area, which is about 4 miles down the loop road from the Visitor Center.

Una Vida from a Distance

There is one site, however, which is accessible by a short walking trail directly from the Visitor Center parking lot.  It isn’t the most impressive of the sites, but it has a certain charm to those who are willing to seek it out.  This site is the great house known as Una Vida.

Una Vida in the Snow

Like most of the other major great houses in Chaco Canyon, Una Vida was first documented and named by the Lt. James Simpson of the Washington Expedition in 1849.  Simpson relied heavily on one of the expedition’s guides, a Hispanic man from the nearby village of San Ysidro named Carravahal, and as a result most of the names he wrote down for the sites were Spanish.  “Una Vida” (meaning “One Life”) is one of these; the reason for the rather odd name is obscure.

Walls at Una Vida

Unlike most of the other great houses, Una Vida looks today much as it did when Simpson first saw it.  We often describe it as “unexcavated,” but this isn’t strictly true.  A few rooms in Una Vida were excavated at various times during the twentieth century, but they have all since been backfilled, so while there has been a bit of excavation it isn’t apparent from looking at the site.  As a result, Una Vida is one of the best places to see what the sites looked like before being excavated.  Basically, it looks like a huge mound of sand, covered with shrubby vegetation, with significant standing walls sticking out at various points.  It’s clear that there is a building there, and it’s clear what its overall size and shape is, but it isn’t clear how many rooms it contains or where the divisions between them are.

View from Plaza of Una Vida

Moving up to Una Vida from the parking lot and entering the plaza, one is surrounded by high mounds of sand, which obscure most of the building and the ridge upon which it is built.  It is hard to tell from here quite what the building would have looked like when it was in use, but it’s quite obvious that it was very impressive in scale.

Navajo Corral at Una Vida

Looking around the plaza, there are a few enclosures of varying sizes made out of the same sort of stone found in the walls of the great houses but with very different masonry, dry-laid without any mortar.  These were actually not present when Simpson came by in 1849, but were built later by the Navajo inhabitants of the canyon.  They weren’t here in 1849 because the Washington Expedition had been sent to fight the Navajos, who weren’t about to wait around to be attacked.  After the conclusion of the tumultuous wars between the US government and the Navajos with the return of the Navajos from the ill-fated reservation at Bosque Redondo in southeastern New Mexico in 1868, however, the canyon was reoccupied and the Navajos built a variety of structures, many of which are still standing in some form.

Navajo Hogan at Una Vida

In general the Navajos avoid ruined sites like Una Vida.  Navajo tradition involves a lot of taboos about death and places associated with it, and sites associated with the Anasazi are particularly problematic.  There is very little trace of Navajo occupation in the Downtown Chaco area around South Gap and Pueblo Bonito, for example.  In some other parts of the canyon, including the Fajada Gap area where Una Vida is, certain Navajos seem to have been less concerned about the taboos and, perhaps, more inspired by the abundant building stone from the fallen walls.  In any case, they built a few hogans (traditional Navajo dwellings) and a large corral in the plaza of Una Vida, and the remnants of these can still be seen today. In general there is little trace of the Navajo presence at Chaco within the park today, due in no small part to deliberate Park Service policy in the mid-twentieth century that involved kicking out the Navajos living in the park.  Here at Una Vida, however, some of that history is still visible in a subtle way.

Third-Story Walls with Type I Masonry at Una Vida

Moving on from the plaza to the west wing, one can see the typical row of blocked-in round rooms fronting the plaza and backed by higher stories of rectangular rooms.  This is pretty standard for Chacoan great houses, but here it’s interesting on account of the fact that this room block is made largely of early masonry.  This part of the building seems to have been constructed sometime in the 900s using Type I simple masonry.  It goes up three stories at the south end, and this seems to be the only part of Una Vida that was ever three stories.  The immense height of some other parts of the building is due largely to its being built on a natural ridge.  There’s no evidence for any other construction above two stories.  It’s pretty striking that the three-story rooms are among the best-preserved despite their early masonry.

Petroglyphs above Una Vida

Moving along the west side, one comes to the place where a spur trail leads partway up the cliff to an area of quite remarkable petroglyphs.  These are among the most impressive in publicly accessible parts of the park, and are also among the easiest to get to.  As usual with rock art, they are difficult to interpret, but some clearly seem to show animal figures which may be either highly stylized representations of real animals or images of mythical or legendary beasts.  There is also an anthropomorphic figure with two horns which has been identified by Hopi consultants as a symbol of the Two-Horn Society.

Una Vida from Petroglyph Area

From the petroglyph site, one can get a very good view of Una Vida and finally get some sense of its overall size and shape, which is particularly difficult to get a sense of from ground level because of its unexcavated nature.  It’s basically L-shaped, with an arc of plaza-enclosing rooms linking the ends of the L.  Fajada Butte, Fajada Gap, and the Visitor Center are also clearly visible from up here.

Visitor Center and Fajada Butte from Una Vida Petroglyphs

Coming back down from the petroglyphs and continuing along the trail, next comes the earliest part of Una Vida, a small block of rooms built in the 800s and later shored up with what looks like McElmo-style masonry (typical of the early 1100s).  This block is similar to the oldest part of Pueblo Bonito, which was built around the same time, and it’s likely that Peñasco Blanco, which has tree-ring dates from the same period, has a similar early block somewhere, although given its unexcavated state it’s impossible to identify it.  These three early great houses, the earliest in Chaco Canyon, are located at the three main entrance points to the canyon: Fajada Gap, South Gap, and the end of the canyon where the Escavada Wash and the Chaco Wash join together.  This is likely not a coincidence.

Earliest Part of Una Vida

Continuing along the trail, the next notable part of the site is a single room with particularly well-preserved standing walls and an intact doorway.  This part of the site, the east wing, is a later addition using Type IV core-and-veneer masonry, which is quite apparent in this room.

Doorway at Una Vida

Finally, the trail comes back to the Navajo corral and completes the loop, heading back toward the Visitor Center.  Although there is less to see at Una Vida than at, say, Pueblo Bonito, its mostly unexcavated state and unusual features offer a window into some aspects of Chaco that don’t get that much attention, and it’s definitely worth a visit.

Lizard on Type I Masonry at Una Vida

Read Full Post »

A Virtual Tour of Chetro Ketl

Chetro Ketl Sign

Most of the major great houses in Chaco Canyon were first named and documented by the Washington Expedition in 1849.  Lt. James Simpson, a military engineer tasked with surveying the country the expedition passed through as it campaigned against the Navajos, took detailed notes and measurements about the sites, and in his published report on the expedition first brought them to the attention of the American public.  For his information on the sites Simpson relied on the expedition’s guides, and particularly on one in particular: a Hispanic man from the nearby village of San Ysidro identified as “Carravahal.”  His first name never seems to be given in publications about Chaco, starting with Simpson’s, but he clearly belonged to the well-known Carbajal family of New Mexico, and it would probably not be very difficult to figure out his first name and other background information on him.  He seems to have been quite familiar with the sites at Chaco, more so than the expedition’s Navajo or Pueblo guides, which implies that people in San Ysidro and other local villages had been coming out into the Chaco area for a while at that point.

Side Wash by Chetro Ketl

As a result of Simpson’s greater reliance on Carravahal than on the other guides, the names he recorded for the sites were generally those given to him by Carravahal, and that generally meant they were Spanish names.  It is not clear if Carravahal was giving the names used by people in San Ysidro for specific sites or making up names as went along (perhaps it was a mixture of both), but most of the names he gave were either very generic (“Pueblo Bonito” = “Pretty Town”) or simply descriptive (“Pueblo del Arroyo” = “Town of the Wash”).  Some of Carravahal’s names, however, were not Spanish, and it’s not clear what language they were from or where he got them.  Among these is the name he gave to the large site east of Pueblo Bonito, which he gave a name that Simpson transcribed as “Pueblo Chettro Kettle.”  Either Carravahal himself or some other guide apparently claimed at one point that this meant “Rain Pueblo,” but without any further elaboration.  No one has ever figured out what the name, now usually spelled “Chetro Ketl,” means or where it comes from.

Chetro Ketl, the Talus Unit, and Pueblo Bonito from the Cliff Top

Chetro Ketl is one of the largest and most interesting of the great houses in Chaco Canyon, but it often gets overshadowed by Pueblo Bonito.  The two are right next to each other, and are in fact accessed today from the same parking lot.  They are separated only by an open area that probably played an important role in the Chaco system.  There is increasing evidence that the acoustic properties of the canyon wall along this stretch were important, and parts of the canyon wall even seem to be sculpted to improve their acoustic properties.  This is what is known as the “Chaco Amphitheater,” and its location right in between Pueblo Bonito and Chetro Ketl is likely significant.

"Chaco Amphitheater" between Pueblo Bonito and Chetro Ketl

In any case, while Pueblo Bonito is generally considered the largest of the great houses, and therefore probably the most important, Chetro Ketl is actually the second-largest by most measures and the largest by at least one.  Although Pueblo Bonito is certainly more massive and had a lot more rooms, Chetro Ketl is slightly larger in area.  By whatever measure, however, the two sites are very nearly the same size, and may well have been equally important in the Chacoan system.

Plaza-Enclosing Rooms at Chetro Ketl

It is by no means clear what the functions of any of the great houses may have been, but it is certainly possible that Pueblo Bonito and Chetro Ketl fulfilled somewhat different functions, given their similar scale, physical proximity, and rather different (though similar) shapes.  While both are “D-shaped” in some sense, and both face south in that the highest levels are on the north side and subsequent rows of rooms terrace down toward enclosed plazas on the south side, they are not quite the same.

Pueblo Bonito from Above

Pueblo Bonito has a unique form, with the curved part of the “D” forming the tall back wall and the straight part of the “D” forming the roomblocks enclosing the plaza on the south side.  Chetro Ketl is the other way around, with the tall back wall being the straight part of the “D” and the curved part forming the plaza-enclosing block of rooms to the south.  This is a much more typical shape for a Chacoan great house, with Hungo Pavi, Pueblo Alto, Pueblo del Arroyo, and Tsin Kletzin within the canyon (or above it) having nearly identical shapes, though different sizes and periods of construction.  With the exception of Pueblo del Arroyo, which is unusual in many ways, these all face south as well.  This shape is often found at outlying great houses outside the canyon as well, with the three main great houses (east, west, and north) at Aztec being probably the best-known examples.

Chetro Ketl from Above

Chetro Ketl, then, is much more of a “typical” great house than Pueblo Bonito, which is unique in all sorts of ways, including the fact that it is by far the best known and most extensively studied of the great houses.  Chetro Ketl has been partly excavated, with about half of the site having been dug by the University of New Mexico field schools in the 1930s, and much of the site, mostly in the central part, is still exposed and available to be seen today.

Corner Doorway at Chetro Ketl

These excavations, however, were nowhere near as extensive as the earlier excavations at Pueblo Bonito, which resulted in the excavation of almost every room, nor were they nearly as well documented.  The students who did most of the work were not the best about documenting what they were doing, and Edgar Lee Hewitt, the towering figure in New Mexico archaeology who was in charge of the field schools, never got around to writing a full site report which might have clarified the confusing documentation of the students and collected the information from the digs in an accessible area.  As a result, Chetro Ketl is not nearly as well understood as Pueblo Bonito, and it isn’t clear if the latter’s fame and presumed centrality are due to its actual importance or merely the greater amount of information available on it today.

Back Wall of Chetro Ketl

Be that as it may, Chetro Ketl is certainly an interesting site to see.  One of the most impressive aspects of it is its back wall, which is the longest wall known at a Chacoan site.  It is not only very long but extremely straight, a true triumph of Chacoan engineering.  It was actually originally even longer than can be seen today, because the extreme east and west ends have not been excavated and still lie under mounds of sand.  It is on account of this back wall, in conjunction with the curved arc of rooms on the opposite side, that Chetro Ketl claims its position as the largest great house in area, even larger than Pueblo Bonito.  The way to enclose a very large area, of course, is to be bounded by very long walls, and Chetro Ketl certainly is.

Back Wall of Chetro Ketl from the Talus Unit

The western end of the part of the back wall visible today, which is the first part one reaches when approaching from the parking lot, is made of Type II core-and-veneer Bonito-style masonry, much like the early expansion of Pueblo Bonito.  This is hardly surprising, since this part of Chetro Ketl dates to the AD 1030s or so, while the similar masonry at Pueblo Bonito dates to the 1040s.  While at Bonito this type of masonry is part of a significant expansion of what was by then a very old building, here at Chetro Ketl it is the earliest part of the building standing today (although there may have been some earlier construction that was built over at this time).

Type IV Masonry at Chetro Ketl

As one moves eastward along the back wall, the masonry changes.  The outer wings of Chetro Ketl were added later in the eleventh century, and they show a steady progression through Types III and IV.  At the part of the building showing Type IV masonry the trail leads inside.

Central Roomblock at Chetro Ketl

Once inside the building, many rooms are apparent, most of which have been excavated and largely backfilled, especially in the central roomblock with the prominent elevated round room known as Kiva G at its heart.  To the east, the far east wing has not been excavated and the decayed nature of the walls is very apparent.  While they have been stabilized, there has been no excavation or reconstruction of this part of the building.  These rooms are all quite similar to those in the later parts of Pueblo Bonito, and they are in many ways just as mysterious.  There is little evidence for their function, and while some show evidence of residential use, most don’t.

Elevated Kiva G at Chetro Ketl

Continuing along the trail, one reaches the plaza.  Chetro Ketl’s plaza is distinctive in a number of ways.  For one, it’s very large.  Again, since Chetro Ketl has fewer rooms than Pueblo Bonito but is nonetheless larger in area, a much greater proportion of its area is taken up by the very large plaza.  Also, and perhaps more distinctively, the plaza at Chetro Ketl is elevated.  While most great-house plazas are at or near grade, this one was filled to about 12 feet above grade, apparently gradually as the building was expanded (with the eventual result that the first stories of some earlier rooms ended below the plaza level).  It is unclear why this was done, and it is especially unclear why it was apparently only done here and not at any of the other great houses with enclosed plazas.  It would certainly have been an enormous amount of work, but then the Chacoans were by no means averse to enormous amounts of work on projects that today seem inscrutable.

Chetro Ketl Great Kiva from Above

As a result of the raised plaza, the great kiva at Chetro Ketl, while it seems subterranean, is actually considerably above the original ground level.  It is one of the largest and most impressive in the canyon, and shows the usual set of standard features: bench, central firebox, four postholes (one of which, when excavated, contained part of the original post, an enormous ponderosa pine trunk), entry by steps from an antechamber on the north side, many niches in the wall, and two vaults on the floor flanking the firebox between the postholes.  There are also some large sandstone disks sitting around the northeast posthole.  These disks were originally in the postholes, where they served to support the posts and keep them from driving right down into the soft alluvial soil.  There were generally multiple ones in each posthole.  They are a standard feature, almost always found during excavation, but not usually displayed like this.

Great Kiva at Chetro Ketl Showing Three Levels

Also displayed in an unusual way here are multiple levels of the great kiva.  While great kivas typically have multiple floor levels and accompanying layers of features, excavators usually decide to present the kiva at one particular level and obscure evidence of others (which have often been destroyed during excavation anyway).  Here, however, the excavators left a quarter of the floor excavated to a lower level, showing an earlier bench and some niches of decided different shape, size, and spacing from those in the later level above.  They also left a small section of an even later bench level in place.  This bench is made of very crude masonry and was probably much later than the earlier levels.

Colonnade at Chetro Ketl

Perhaps the most interesting part of Chetro Ketl, and certainly one of the most mysterious and evocative, is found at the part of the north-central roomblock facing the plaza.  Here, in rather late masonry style, is a series of square columns, later filled in by even later and cruder masonry to form an unbroken wall.  This is the famous Colonnade, one of the most prominent examples of possible Mesoamerican architectural influence at Chaco.  Colonnades like this are vanishingly rare in the southwest, but they are quite common in Mesoamerica during the period contemporaneous with Chaco (the early postclassic).  They seem to have originated in northern Mexico, but they spread throughout the Mesoamerican cultural sphere, with famous examples at Chichen Itza, far to the south on the Yucatan Peninsula, and at Tula, much further north in central Mexico, along with numerous other lesser-known instances elsewhere.

Partly Walled-Up T-Shaped Doorway at Chetro Ketl

In the 1970s, the “Mexicanist” school of Chacoan interpretation proposed this colonnade at Chetro Ketl as an example of what they claimed was intense Mesoamerican influence at Chaco.  Other examples they pointed to were T-shaped doorways, relatively uncommon in the southwest but very common in Mexico and present, often in significant locations such as facing plazas, at Chaco, and trade goods like copper bells and macaws that clearly came from far to the south.  The “Indigenist” camp of opposing scholars, however, pointed out that these architectural influences were very subtle and quite possible coincidental, that the trade goods were present in extremely small numbers, and that the extent of Mesoamerican influence proposed by the Mexicanists was by no means supported by the limited evidence for contact with cultures to the south.  These arguments largely won out, and recent theories of Chaco have generally focus on its indigenous context and local nature, with Mexican influence downplayed considerably.

Partly Walled-Up T-Shaped Doorway at Chetro Ketl

Very recently, however, the discovery of chocolate in cylinder jars at Pueblo Bonito has provided incontrovertible proof of a much more direct and meaningful connection to Mesoamerican cultures than had been known before, and this is likely to make things like the Colonnade, even if subtle and present in small numbers, seem more important to the essence of Chaco.  There will certainly be increasing amounts of research on these questions in the years to come, and the Colonnade at Chetro Ketl is likely to be in for some renewed scrutiny, particularly given its apparently late date of construction and even later date of sealing-up.  This is just one example of how right now is a great time to be at Chaco and seeing the place, including mysterious but important parts of it like Chetro Ketl, with new eyes.

Plaza at Chetro Ketl

Read Full Post »

A Virtual Tour of Pueblo del Arroyo

Pueblo del Arroyo Sign

Pueblo del Arroyo, the latest and smallest of the large “Bonito-style” great houses in Chaco Canyon, is an interesting site for a variety of reasons.  It occupies a transitional place in the history of the canyon, both between the Bonito phase and the succeeding McElmo phase and between the era of the Chaco system as a whole and whatever it was that succeeded it.  Although it was built later than many other large sites in the canyon, and thus had a shorter period of overall occupation, it still shows a considerable amount of change over time that illustrates larger-scale changes that are not as visible at the older, more complicated sites such as Pueblo Bonito.

Northwest Corner of Pueblo del Arroyo

The northwest corner of Pueblo del Arroyo is the first part of the site one reaches when walking up from the parking lot.  This part of the site, the north wing, is unexcavated, and it offers a good opportunity to see what the rest of the sites looked like before excavation.  There are a considerable number of standing walls, showing the overall size and shape of the building, but most of the lower stories, especially the first story, are still mounded over with windblown sand.  This sand, which filled in the lower stories which were protected by thick walls and prevented from falling down like the upper stories, still protects whatever lies inside these rooms in the north wing.  We don’t know what is in them, but judging from what was found in the rooms elsewhere that have been excavated, it’s probably pretty impressive and well-preserved.  This sand, which protects the contents of the rooms very well, is one of the things that makes Chaco such a well-known and spectacular place: in addition to the fineness of the architecture, the artifacts preserved by the sand are quite impressive as well.

View of Pueblo del Arroyo from Its North Wing

Moving along the west wall of the site and up into the north wing, one can see pretty much the whole site.  In contrast to the larger sites like Pueblo Bonito, Pueblo del Arroyo is a lot easier to get a handle on.  It’s small enough for the whole thing to be readily visible from the upper parts of the north and south wings.

Latilla Holes at the Oldest Section of Pueblo del Arroyo

The earliest construction stage at Pueblo del Arroyo took place between around 1065 and 1075 AD.  This was the back portion of the central roomblock, starting with the west wall.  It was three rows wide and approximately the same length as the final central roomblock, although some parts may have been covered over by later construction of the wings.

Later, between about 1095 and 1105 AD, two wings were added to this roomblock, one on the north side and one on the south side.  These are pretty similar to each other, although they differ in a few ways.  They both consist of one or two central elevated round rooms surrounded by rectangular rooms to form an overall rectangular shape.

Kiva Pilasters at Pueblo Del Arroyo

The north wing, which originally went up three stories, has two round rooms at its center, one on the second-story level and one on the third.  The one on the third story has been excavated and is the only part of the north wing to be excavated.  It is a good example of a “Chacoan” style round room (or “kiva”), with an encircling bench containing several pilasters, cube-shaped masonry blocks with radial logs inside them.  The function of the logs is obscure, but the pilasters as a whole served as bases for the logs that were laid across them and then built up to form a cribbed roof, sort of a false dome with a smoke hole in the center that also provided access to the room via ladder.  As the presence of a smoke hole implies, there was also a hearth on the floor of the room (now covered up in this case, like the other floor features, by backfill).  On the south end of the room is a vent shaft, which brought in air from outside and could open either at the level of the bench or through the floor.

In addition to the internal features, the main thing that distinguishes “Chacoan” round rooms from others is their positioning within the site.  Unlike many other round rooms, which are subterranean or semi-subterranean, these rooms built above-grade into the square roomblocks around them.  This is a distinctive feature of Chacoan sites, but it’s pretty mysterious.  It’s totally impractical structurally, as it creates four small corner rooms that are generally pretty useless and, indeed, are usually used to buttress the round room, either with logs set across them or by being filled in entirely.  Whatever the purpose of the blocking-in, however, it is a typical feature of Chacoan sites.

Bonito-Style Masonry atop McElmo-Style Masonry, Pueblo del Arroyo

Another more unusual feature of this particular round room can be seen where the fill has been cut away to reveal a lower level of masonry below the main bench level.  This masonry is quite different from the fine “Bonito-style” masonry above it, which uses the hard, tabular sandstone quarried on top of the mesas that is typical of the masonry in Bonito phase great houses.  Instead, it is made of larger blocks of the soft, yellowish sandstone found at the base of the cliffs.  It resembles the “McElmo-style” masonry seen in the construction of sites such as Kin Kletso, which is quite close to Pueblo del Arroyo and visible from the north roomblock.  These sites seem to have been built in the early 1100s, toward the end of the Chaco era, and their style is therefore generally thought of as later than the “classic” Bonito style.  Pueblo del Arroyo, however, was built over a period that seems to been transitional between the two styles, and the north roomblock especially shows several places where Bonito-style and McElmo-style masonry seem to have been used at the same time, often, as in this round room, with the “later” McElmo masonry below the “earlier” Bonito masonry, clearly showing that McElmo masonry is not necessarily later than Bonito masonry at all.  Explaining this is difficult, and Pueblo del Arroyo seems to be the only site that shows this sort of thing on this scale.

Burned Kiva at Pueblo del Arroyo

The south wing, unlike the north, has only a single blocked-in round room at its center, at the second-story level.  This room is larger than either of the two round rooms in the north wing, but it is otherwise pretty similar to the excavated one there.  The south wing as a whole is also pretty similar to the north wing, except that it went up four stories instead of three.  Both wings consist of a very regular pattern of square rooms surrounding one or two round rooms, which is a pattern very similar to that seen in the later McElmo sites, which are very regular and modular and tend to be made of one or more “units” consisting of one or two round rooms surrounded by square rooms.  (Most McElmo sites have one of these units; Kin Kletso has two.)

Kin Kletso

The two wings of Pueblo del Arroyo, then, both built around 1100, are strikingly similar in plan to the McElmo units of a few years later.  They are generally still made of Bonito-style masonry (although note what I said above about the overlap in styles), but otherwise seem to be precursors of the later sites.  Again, hard to explain, but seemingly unique to this transitional site.

Partial Roof at Pueblo del Arroyo

Another difference between the north and south wings is that the south wing has been excavated, so it is possible to look down from the level of the elevated round room and see quite a bit of the lower stories.  They have been refilled to varying levels, but there is still quite a bit to see, including, in one room, some of the original roof beams showing the style of roofing, which consisted of large beams of ponderosa pine spanning the short axis of the room, crossed perpendicularly above by smaller beams of aspen or other small trees, then covered with juniper splints which sealed in the packed earth that formed the floor of the room above.

Plaza-Facing Rooms at Pueblo del Arroyo

The next stages of construction are harder to date, but they seem to have taken place sometime in the early 1100s.  They are the expansion of the central room block eastward toward the plaza, with the new construction consisting largely of blocked-in round rooms at various levels, and the final enclosure of the plaza within a one-story arc of rooms, forming an overall D-shape to the building.  This shape is quite common for Bonito phase great houses, and it is seen in Chetro Ketl, Pueblo Alto, Hungo Pavi, and a variety of other sites as well.  Interestingly, the sequence of construction of all these sites seems to have been the same as well, starting with the central roomblock, followed by the two wings, then finishing with the enclosing arc of rooms.  This is the case even though the sites were all begun and finished at different times, which implies that they may all have been planned with the final shape in mind from the very beginning.

Despite its rather typical shape and sequence of construction, however, Pueblo del Arroyo is unlike any other great house in the canyon in its positioning and orientation.  While most of the great houses are at the foot of the cliffs on the north side of the canyon and face south, with their highest levels on the north side and the rooms terracing down from there to the enclosed plaza on the south, Pueblo del Arroyo is out in the middle of the canyon, right next to the Chaco Wash (hence its name), and it faces east, with its long, straight back wall with the highest stories on the west side and the enclosed plaza on the east.  This is very difficult to explain.  It could have something to do with its late date, but it’s clearly not the case that there was no room left on the north side of the canyon at the time Pueblo del Arroyo was initially constructed, since Kin Kletso, which was constructed even later, is right at the foot of the cliff quite close to the site of Pueblo del Arroyo.

Kin Kletso from Pueblo del Arroyo

One reason Pueblo del Arroyo might have been placed as it was is apparent from a look at the south side of the building, which is interesting for many reasons.  Like many exterior walls of great houses, this one has no doorways on the first floor but does have several doorways on the second floor (and probably on the third and fourth, which have not survived high enough to tell).  Some of these doorways are T-shaped, an unusual and probably significant shape that has been proposed as a sign of Mesoamerican influence, while others are more typical rectangles.  It may seem a bit odd to have doorways on the upper stories when there are none at ground level, but the reason is actually fairly clear from evidence at other sites such as Chetro Ketl, where there were balconies at the floor levels of the second and third stories on the outside of the building.  Although there is no direct surviving evidence for balconies at Pueblo del Arroyo, it is reasonable to conclude that there were originally balconies and that the upper doorways didn’t serve as entrance points to the building but as exit points from the building to the balconies.

T-Shaped Doorway at Pueblo del Arroyo

If there were balconies on the south side, though (which, remember, is not the front of the building), what were they there for?  What would people see when they walked out onto the balconies?

The answer is clear from turning around and looking south, where a couple of potentially important things are clearly visible.  The first, of course, is the wash, which runs right next to Pueblo del Arroyo.  Keeping an eye on the water flow would be a useful thing to do, for obvious reasons.  The second is perhaps a bit less obvious in its importance, but it’s at least as striking in its effect.  This is the large gap in the mesa to the south directly across from Pueblo del Arroyo.

South Gap from Pueblo del Arroyo

This gap, called South Gap, was one of the three main entrance points to the canyon from the south, and it makes sense that having a building overlooking it would be useful both for monitoring who and what was coming in and for impressing people entering the canyon with the monumental nature of the building.  The early great houses built in the 800s, Pueblo Bonito, Una Vida, and Peñasco Blanco, are all built at or near the gaps (respectively: South Gap, Fajada Gap, and the point to the west where the mesa ends, which is not really a gap but is still an entrance point to the canyon), but Pueblo Bonito is not actually directly across from South Gap.  Pueblo del Arroyo is.  It is hard to escape the conclusion that the odd siting and orientation of Pueblo del Arroyo likely had something to do with this.

Pueblo del Arroyo from South Gap

There’s another odd thing about the south side of Pueblo del Arroyo.  When the south wing was initially constructed, the second, third, and fourth stories of the southernmost row part of the addition were constructed as usual, with long walls subdivided by cross-walls to form a series of rooms.  On the first story, however, there were no cross-walls.  The whole thing formed one extremely long, continuous room.  As a result, the weight of the upper stories was not adequately supported, and the wall began to lean outward.  To stabilize it the builders put up a series of buttresses on the outside, which seem to have worked, and the wall is still standing and in fairly good condition today.

South Addition to Pueblo del Arroyo

Much later (although it’s impossible to say exactly when), someone (it’s impossible to say exactly who) came along and turned these buttresses into the cross-walls for a series of rooms built along the south wall of Pueblo del Arroyo using very crude masonry.  These rooms show lots of evidence of residential use, so we do know what the people were doing in them, but beyond that it’s very difficult to say why they built them.  They do seem to have used at least some rooms inside Pueblo del Arroyo as well, so it wasn’t that they didn’t have access to the building.  This was likely long after the fall of the Chaco system,  probably in the late 1100s or even later, and it’s a good example of the changes that took place in the canyon after the end of its regional importance.  For some reason these changes are much more apparent here at Pueblo del Arroyo than at other sites.

Modern Erosion-Control Measures in Chaco Wash at Pueblo del Arroyo

Walking around the southwest corner of the building, one can see just how close the wash comes to the building.  There are a variety of erosion-control devices visible to keep the wash from eating away at the building any more than it already has.  There are also many preservation measures apparent to drain water away from the building and into the wash, most notably a downspout and pipe that the preservation crew painted to blend in with the surrounding masonry.  It’s one of their more whimsical efforts.

Drainage Pipe at Pueblo del Arroyo, Painted to Blend In

Perhaps the most spectacular example of the post-Chacoan changes at Chaco that can be seen at Pueblo del Arroyo is on the west side.  Built right against the back wall of the building is a remarkable and mysterious structure built of three concentric circular masonry walls, with the two outer rings divided into rooms by radial walls.  The masonry style indicates that at least most of this structure is clearly later than the rest of the building, being more like the classic McElmo style of the early to mid-1100s.

Tri-Wall Structure at Pueblo del Arroyo

This is an example of what is known as a “tri-wall structure.” It’s the only one at Chaco, but not the only one anywhere.  They are mostly associated with the area to the north of Chaco, which was rising in importance regionally during the 1100s at the same time that Chaco was declining.  There are tri-walls in the Mesa Verde area, and they are particularly associated with the Totah area along the middle San Juan river valley.  There are at least three of them at Aztec Ruins, which seems to have become a major regional center around this time.  This one at Pueblo del Arroyo, then, seems to indicate influence from the north in the post-Chaco area, although beyond that it’s hard to say much about it.  It has been excavated (and later backfilled for preservation), but the excavations found that it had been substantially dismantled in antiquity, apparently for building stone.  It’s not clear where the stone was used, but the row of rooms along the south side of Pueblo del Arroyo is one obvious possibility.

Hubbard Tri-Wall Structure at Aztec Ruins National Monument

Because of the disassembly, not much was left to indicate the function of the tri-wall.  Despite its round shape, however, it bears little resemblance to other round rooms such as great kivas.  Most other round rooms of whatever size and shape have hearths in the center, but the tri-wall doesn’t.  Instead, the innermost circle has a flagstone floor.  This is a very unusual feature, as rooms in these sites almost always have earthen floors, but it is known from some other sites where it seems to be a functional aspect of storage rooms used to keep rodents out.  Here, however, it likely has some more esoteric purpose.

The prevalence of tri-wall structures throughout the San Juan basin during the 1100s, and their absence before and after, seems to indicate that they were associated with a short-lived flourishing in the immediate post-Chaco era of some sort of regional social or ceremonial system, possibly centered on Aztec.  Since it was so short-lived, however, and no aspect of it seems to have survived in recognizable form into the present-day Pueblos, it is perhaps even harder to interpret than the Chacoan system that it seems to have replaced.

West Wall of Pueblo del Arroyo Showing Addition Associated with Tri-Wall Structure

Coming back around from the tri-wall to the northwest corner, one has circled the entire building.  It is notable that the tri-wall, one of the later, mysterious additions that make Pueblo del Arroyo so interesting, is right up against the west wall, the earliest part of the building, which in a sense brings things full circle.  Despite its relatively short period of occupation, Pueblo del Arroyo shows a lot of change and mystery, which makes it a fascinating place deserving of much more attention than it usually gets.

View from Doorway at Pueblo del Arroyo

Read Full Post »

A Virtual Tour of Pueblo Bonito

Pueblo Bonito Sign

Pueblo Bonito is the best-known of the great house sites in Chaco Canyon, among the most fully excavated, and by at least some measures the biggest.  Even from a distance, such as from the parking lot from which one approaches it, it looks massive and imposing.  As, indeed, it is, and it is in mass (number of rooms, amount of masonry, etc.) that it claims the title of largest great house.  In area Chetro Ketl, another great house right next to Pueblo Bonito, is actually slightly larger.  But it is Pueblo Bonito that has claimed the greatest amount of publicity, for a number of reasons, some better than others.

Pueblo Bonito from a Distance

Part of the way down the trail from the parking lot to Pueblo Bonito is a plaque that has an artist’s rendition of how the building may have looked at its height around AD 1100.  Although there is inevitably a bit of artistic license in reconstructions like this, this particular one is about as accurate as they get given the information available, and it is actually a modification of an earlier rendition taking into account newer research.  One thing that can be seen from this image is the sheer size of Pueblo Bonito.  The little people running around the building are to scale, which shows that this was a very large building indeed in its time.

Pueblo Bonito Plaque

Another thing that can be seen from the artist’s rendition, and perhaps more clearly from the architectural plan view next to it on the plaque, is something of the shape of Pueblo Bonito.  One aspect of the layout that is particularly notable is that there are a lot of straight lines, right angles, and abstract geometrical forms, culminating in the overall D-shape of the entire building.  This regularity is clear evidence that there was a considerable amount of planning involved in the design of Pueblo Bonito.  This is typical of Chacoan great houses, many of which show even more regularity in design than Pueblo Bonito, but it is actually not typical of Pueblo sites in general.  Most Pueblo sites both before and after the Chacoan era (ca. AD 1030 to 1130) show a very different pattern of development, a more functional, organic pattern with one room being added onto another as necessity dictated, with no particular attention being paid to the overall form of the building.  This type of development is typical not only of early sites, but also of sites after the Chacoan era, including the famous cliff dwellings at Mesa Verde, Canyon de Chelly, and Navajo National Monument, which are large and impressive, to be sure, but not particularly planned.

And, indeed, even during the Chacoan era, and even right in Chaco Canyon, we see a very different type of site from the great houses, most of which are on the north side of the canyon.  On the south side of the canyon across from Pueblo Bonito, near the great kiva Casa Rinconada, are a few sites that have been excavated and stabilized which show a very different pattern of development from the great houses, a pattern much more typical of other sites from other times and places.  They don’t show the large scale, planned nature, and elaborate construction techniques that distinguish Chacoan great houses from other Pueblo sites.  These are called “small houses” in contrast to the great houses, and they actually line the canyon from one end to the other, mostly on the south side.  Indeed, there are many more of them than there are great houses, and from tree ring dates we know that they were being built and occupied at the exact same time, and it is now thought that the vast majority of people in the canyon at the time lived in the small houses.

Small House across from Pueblo Bonito

This leaves us with a bit of a mystery.  Why were there two very different types of sites being built and used in the same place at the same time?

It’s actually an unsolved mystery, and only one of many such mysteries about Chaco Canyon.  Most of these mysteries center on the great houses, which remain puzzling in many ways despite having been intensively studied for over a hundred years.  That century of research has resulted in some answers to be sure, but it has raised at least as many questions.  There are things that we do know.  We know a lot about when they were constructed and how they were constructed, but we know very little about why they were constructed and what their function was, and indeed what was going on that made Chaco such an important place in its time.  These are, of course, many of the most interesting things about the great houses, and the things we might most like to know.  Many theories have been proposed to bridge the gap between what we know and what we would like to know, but they’re all based on the same rather meager evidence, supplemented with a considerable amount of speculation, and as a result they conflict quite a bit.  Thus, in the remainder of this post I will be focusing mostly on the things we do know from the archaeological record, which are the building blocks out of which the theories are constructed, and leaving the theorizing to my readers, since, to a remarkable degree, your guess is as good as anyone’s about what was going on in Chaco.

Type IV Masonry at Pueblo Bonito

The southeast corner of Pueblo Bonito is a good place to see the fine masonry for which Chaco is justly famous.  Most of the stonework visible here is original; the mortar is not.  You can see various types of mortar here, including some Portland cement, some other types of cement, and some mud.  The original mortar was mud-based, and it held the walls together fine while the building was being used and maintained.  Then, over the hundreds of years during which the building was no longer in use and was gradually being filled with windblown sand, the sand kept the walls stable and standing remarkably well.  So well, in fact, that not only were the walls preserved, the contents of the rooms they formed were preserved remarkably well, and when they were eventually excavated the excavators found an astonishing variety of artifacts, including many made from perishable materials that don’t typically survive so long.  Once the building was excavated, however, and the walls were exposed to the wind and rain they began to deteriorate pretty rapidly, and one of the first things to go was the mud mortar when it was exposed to the wind and rain.  Thus, the park now has a full-time preservation crew that goes around to each of the buildings and does whatever it takes to keep them standing.  One of the main things they do is touch up the mortar, typically by pushing new mortar into the spaces where the original has fallen out (rather than by redoing the stonework entirely).  Early on they used Portland cement, but over the years understandings of material properties have improved and it is now known that Portland cement is not a good material to use for this, for a variety of reasons not least of which is that it has different properties from the original mud, which remains in significant quantities inside the thick walls.  One of the most important differences is the rate at which the  materials expand and contract during annual freeze-thaw cycles, with the result that different parts of the walls end up moving at different rates over the course of the year, which actually tends to destabilize the walls a bit.  Thus, the preservation crew at Chaco has moved toward other types of cement that mimic the behavior of the mud more, as well as mud, which mimics the behavior of the mud exactly, but one of the ways in which it does so is that it falls out easily and has to be replaced a lot.  What material to use in each situation is a judgment call to some extent, and the crew makes different decisions in different places.

Walls at Pueblo Bonito Showing Capping

Another thing the preservation crew does is capping.  The top foot or so of every wall is modern capping, which is done in the same style as the original masonry but often using a slightly different color of sandstone.  This can be seen clearly in some parts of the southeast corner of Pueblo Bonito, including the part in the picture above, where the reddish sandstone is original and the lighter sandstone toward the outside of the wall is the capping.  This capping is done to stabilize the walls and keep them from falling down, which is a constant risk when they are exposed.  Again, early on they used Portland cement for this, but more recently they’ve shifted to other types of cement that work better in context.  You can’t really use mud for this, because the important thing is that it stay on.  You don’t want any risk of that capping coming off or the walls will fall down.

Southeast Corner of Pueblo Bonito from Threatening Rock Overlook

Continuing on from the southeast corner, one comes to an overlook from which (almost) the entirety of Pueblo Bonito is visible.  Many things are visible from here, one of which is that the part of the building that is visible from the parking lot and the trail leading from there toward the building is just the southeast corner; the entire building extends considerably further to the west.

Western Half of Pueblo Bonito from Threatening Rock Overlook

This overlook was not always there.  It was built atop the remains of a big rock that fell on Pueblo Bonito on January 22, 1941.  This rock was called “Threatening Rock,” and the name was apt.  It looked somewhat like another rock that still leans out over the canyon floor just east of Pueblo Bonito, visible from the overlook, but it was about four times as big.

Rock Leaning Threateningly from Canyon Wall

When it fell, Threatening Rock crushed about thirty rooms of Pueblo Bonito that had already been excavated, but it also provided the Park Service with a nice little overlook, so there was at least a bit of a silver lining.  The amount of fallen rock still in place is impressive, particularly when one considers that it was all originally a single rock.

Rubble from Threatening Rock

On top of the overlook there is a nice plaque that illustrates the various construction stages of Pueblo Bonito.  The building wasn’t built all at once, but in a series of construction stages over the course of about 300 years.  The first stage, starting around AD 850 and continuing through the 930s, was an arc of rooms with an open plaza in the middle containing some kivas.  This was not an unusual layout for a Pueblo site of this period, and this part of Pueblo Bonito is notably less regular than later parts.  Pueblo Bonito was, however, pretty distinctive even at this early date, in that it was much larger than other Pueblo sites.  The rooms were much larger than in other sites, and the building was three stories tall in places, whereas other buildings in the region were at most one story tall in this period.

Plaque at Threatening Rock Overlook

Once the first stage of construction was complete, the building remained more or less the same for the next hundred years.  Then, in the 1040s, as the Chacoan era was beginning and the Chaco system was gearing up, a lot of changes took place in the canyon, and among those was the expansion of Pueblo Bonito.  This expansion took the form of the wings of the arc being extended and the plaza being enclosed by a straight wall on the south side, forming for the first time the D-shape and enclosed plaza that became hallmarks of the Chacoan great-house style of architecture.

Once that stage was complete, the Chacoans just kept building, with extensions and expansions coming fast apace for the next hundred years in a confusing welter of changes that are very difficult for us to untangle.  By the early 1100s it had reached more or less the final state that we see today.

Pueblo del Arroyo from Pueblo Bonito

Another thing that is quite noticeable from atop the Threatening Rock overlook is that Pueblo Bonito is not the only building in its immediate vicinity.  Indeed, there are buildings all around it: Pueblo del Arroyo, just to the west; Kin Kletso, a little further west at the foot of the cliff; Chetro Ketl, across a flat area to the east; Casa Rinconada, across the canyon to the south; and the small house sites, which do line the canyon from one end to the other but are particularly concentrated in this area around Casa Rinconada and across from Pueblo Bonito.

Kin Kletso from Pueblo Bonito

A considerable amount of architecture, then, all around Pueblo Bonito.  And it’s not just architecture, either; there are also roads, mounds, flattened open areas, and various other types of landscaping tying the buildings all together.  This, then, is not just a group of unrelated buildings separated by stretches of untamed vegetation, as it looks today. At the time it was developed, this was a deliberate effort at putting together a large-scale arrangement of buildings and landscaping.  It is interesting to note that, except for a few of the small houses, all of these other buildings were built after Pueblo Bonito had been there for quite some time, mostly in the period when Pueblo Bonito was being expanded.  This, then, may lead us to wonder why Pueblo Bonito was put where it is in the first place.  (It may also lead us to wonder why any of this is in Chaco Canyon in the first place, which is a considerably harder question to answer.)

South Gap from Pueblo Bonito

Within the canyon, however, this is a pretty good place to put a big, important building, and that’s because of something else that can be seen from the Threatening Rock overlook: South Gap, one of the three main gaps in Chacra Mesa to the south that provide the three main entrances to Chaco Canyon.  These three entrance points are South Gap, Fajada Gap to the east where Fajada Butte and the current park visitor center are, and the point to the west where the Escavada Wash comes in from the north and joins with the Chaco Wash to form what is called the Chaco River (which is still a wash).  It is at these three entrance points where we find the three earliest great houses, each built around the same time, with the same construction style, similar layouts and similar sizes: Pueblo Bonito at South Gap, Una Vida at Fajada Gap, and Peñasco Blanco where the Chaco and Escavada Washes come together.  Over the next two hundred years all three of these great houses were expanded considerably and had other buildings built around them, but Pueblo Bonito was expanded considerably more than the other two and had much more built around it.  In this connection, it is interesting to note that South Gap is the central of the three entrance points.  This part of the canyon, then, was the center.  It is an area that archaeologists today often call “Downtown Chaco,” which I think is a good way to think about it.  Pueblo Bonito, in turn, is the center of Downtown Chaco, which is the center of the canyon, which is the center of the Chacoan world.  It is the center place, the most important of all the great houses, and thus the one that is the most frequently visited and toured, as well as the subject of this virtual tour.

Old Bonito

Moving along the back wall of Pueblo Bonito and inside the building, one comes to the oldest part, unimaginatively called “Old Bonito.”  This is the original arc of rooms built beginning around the AD 850s and continuing up to around the 930s.  One of the most striking things about the remains of this early building stage is the masonry, which is quite different from the later, better-known Chacoan masonry.  The difference can be seen in many places in and around Old Bonito where early and late masonry are both present.

Type I Masonry at Pueblo Bonito

This early masonry, known as “simple” or “Type I” masonry, basically consists of unshaped sandstone slabs laid together with a lot of mortar then plastered over on both sides with a mud plaster.  It works well enough, and with the size of rooms used in Old Bonito the Chacoans were able to go up three stories with it, and for the hundred years when that was the whole building it stood acceptably (though some have argued that it was not very stable at that height).  When the building was expanded in the 1040s, however, it was expanded not only out but up, with high-ceilinged rooms going up three, four, and possibly even five stories in the back.  For that scale of building, the Type I masonry was not going to work; it’s just not strong enough.

Core-and-Veneer Masonry: Core

To deal with this problem, the Chacoans invented a new type of stronger masonry that would become closely identified with Chacoan great-house architecture over the course of the Chacoan era.  We call this “core-and-veneer” masonry, and it is basically composed of two parts: a core of rubble and unshaped sandstone blocks, laid together with mortar, and a structural veneer of sandstone blocks that are left rough on one side and hooked in with the core blocks and finely shaped on the other side and laid in elaborate patterns and courses, the styles of which change over time and provide a rough dating system for different parts of buildings.  This veneer was then plastered over, just as the earlier Type I masonry had been, so it would not actually have been possible at the time to see the fine stonework that we today find so impressive about Chacoan masonry.

Core-and-Veneer Masonry: Veneer

The advantage of this core-and-veneer style from a structural perspective is that you can make that core as thick as you want just by putting in more rubble and blocks and then slapping on the veneer; the core and the veneer support each other.  That is, you’re not limited by the size of the stones you happen to have, as you are for the simple masonry.  Thus, this type of masonry can be used to make very thick walls, and that’s exactly what it was used for.  The back walls of Pueblo Bonito are built thick enough at the base to support five stories.  We only see remnants of four stories, but some archaeologists think there was a fifth story in some places, because the walls could support it.  They taper as the go up, to reduce the load on the lower walls.  All in all, a very sophistocated style of construction, particularly given the technology being used for it.

Type II Wall Abutting Type I Wall at Pueblo Bonito

However, another thing that can be clearly seen in Old Bonito is that the Chacoans did not tear down the part of the building built with the older, weaker type of masonry when they developed the newer, stronger type.  Instead they encased it within the newer walls.  Whether this was intended to protect the older part of the building is one of those things that are impossible for us to know for sure, but it certainly did protect large portions of Old Bonito, preserving them well enough that we can see substantial parts still standing today.  This seems to indicate that the older part of the building continued to be important even after the expansions that transformed Pueblo Bonito into a much larger and somewhat different structure.

There are other things about Old Bonito that indicate its continuing importance, particularly the artifacts that were found there.  In addition to being the oldest part of the building, this was one of the first parts to be excavated.  When it was excavated, the excavators found some truly remarkable artifacts, in both quantity and quality, in some of the rooms.  Many of the rooms contained hundreds or even thousands of elaborate, valuable artifacts, most of which seem to have been ceremonial in function (prayer sticks, cylinder jars, etc.), just lying there.  These were apparently caches of ritual objects, though the exact reason the objects were being cached remains mysterious.  The sheer quantity of them, however, indicates that whatever the purpose, it was strongly identified with this particular part of Pueblo Bonito.  Nothing similar was found anywhere else in Pueblo Bonito, or indeed elsewhere in the canyon.

Another type of evidence for the continued importance of Old Bonito, also found by the early excavators, was burials.  Surprisingly few burials were found in Pueblo Bonito overall, given its size and the assumption, generally held by the excavators, that it was a large residential community comparable to modern pueblos.  About 130 burials were found total throughout the building, which is not a trivial number, to be sure, but considerably less than would be expected in a site with at least 600 rooms occupied for over 300 years.  This puzzled the early excavators, who went around looking in vain for outside cemeteries.  Today it’s widely thought that this probably just indicates that there were never very many people actually living at Pueblo Bonito or the other great houses; that is, while they do show some evidence of residential use, for most of their occupation they were not primarily residential in function.

In any case, those 130 burials in Pueblo Bonito were mostly concentrated in just two parts of the building, both of which are in Old Bonito.  One part was a block of four rooms at the far west end of the arc, and the other was another block of four rooms at the north end, the top of the arc.  These burials were, in comparison to typical Pueblo burials at the time, even in the small houses right across the canyon, odd.  Typical Pueblo burials, such as the ones at the Chaco small houses, have few if any grave goods.  A typical grave assemblage would have perhaps a bowl or two, and in rare cases an ornament or other valuable object.  The assemblages at Pueblo Bonito, however, went far beyond that.  What is particularly interesting in addition to the atypically elaborate grave goods is that there was a marked difference between the two burial groups even within Pueblo Bonito.  The ones in the western section had considerably more grave goods than was typical, with the goods being primarily pottery, ornaments, and objects of daily use, found in fairly large quantities but also with a relatively large number of people buried in each room, so the average number of grave goods per burial is fairly low.  The burials in the northern section, however, were unbelievably lavish even compared to the western ones.  While there was a considerable amount of pottery and various other goods in these rooms, the thing that really makes them stand out is the number of ornaments.  One room alone in this section had over 65,000 pieces of turquoise in it, several orders of magnitude greater than any other find elsewhere in the canyon or even, at least to my knowledge, elsewhere in the prehistoric southwest.  Most of these pieces were little beads, of course, but still, that’s a lot of little beads.  There were also considerably fewer people buried in these rooms, raising the number of goods, particularly ornaments, per person to incredible heights.  It’s not at all clear who these people were or why they were buried so lavishly, and theories and opinions among scholars are bitterly divided over the question, but it is clear that whoever they were, they were pretty important, and the place where they were buried, Pueblo Bonito, and more specifically, Old Bonito, was pretty important as well.

Kiva Q and West Plaza, Pueblo Bonito

Moving from Old Bonito into the plaza, one of the first things one sees is a great kiva.  Generally thought to have been primarily ceremonial in function, comparable to kivas at modern pueblos, great kivas are a typical feature of Chacoan great houses, and they are typically found either in the plaza, as here, or just outside of the great house.  One of the fascinating things about Chacoan great kivas specifically (there are other kinds) is their standardization.  The same set of features is found with very limited variation throughout the Chacoan world, which encompasses the whole San Juan basin and a considerable area beyond.  This one, called Kiva Q, is one of the earliest known examples of a Chacoan great kiva, but it already shows the standard set of features.

Floor Features of Kiva Q, Pueblo Bonito

Among the features that can be seen in this great kiva are the encircling bench, the central fire box, and the four circular masonry structures arranged in a square that served as postholes for the large trunks of ponderosa pine that held up the roof.  An intact great kiva roof has never been found, so there isn’t 100% agreement about how roofs were designed and constructed, but enough fallen timbers from the roof are typically found inside that we can get a rough idea.  It’s generally thought that the roof was flat, with the tops of the posts connected by beams to form a square, and timbers radiating out from that square to form a flat ceiling from the inside and a flat roof, covered with mud and packed earth, from the outside.  It is generally thought that there was a smokehole over the fire, and many think that there was a ladder through the smokehole providing access to the great kiva, as is typical at smaller kivas, where this ladder is the only entrance to the kiva.

Entrance to Kiva Q, Pueblo Bonito

Great kivas, however, always have at least one other entrance, so not everyone is convinced of the ladder theory.  This entrance is always either at the north end or the south end (in Kiva Q it is at the south end, while at Casa Rinconada, the largest great kiva in Chaco Canyon, there is one at each end), and it consists of masonry steps leading down from an antechamber.  In Kiva Q the steps only go partway down, and there was presumably a ladder connecting the end of the steps to the floor of the kiva.  This entrance also provided ventilation, and to keep the incoming air from blowing out the fire there is a deflector, which in this case is a grooved masonry structure (unfortunately not really visible in my pictures) that would have held up wooden boards to direct the airflow around the room rather than straight onto the fire.

In addition to those more obvious, structural features of great kivas, there are some other standard features that are a bit more mysterious.  Among them, also unfortunately not visible in my pictures of Kiva Q, are small holes going partway through the wall that we call wall niches.  In Kiva Q there are just four of these and they are at the north end; in many other great kivas, including Casa Rinconada, there are about 30 and they go all the way around.  Their function is not clear.  They are sometimes found with ornaments or bits of turquoise in them, either placed in them or sealed into them, but more frequently there is nothing in them.  In Casa Rinconada some of them seem to have astronomical alignments, but this doesn’t seem to be the case at Pueblo Bonito.  Whatever they were for, they are always there.

Another mysterious but typical feature of Chacoan great kivas is the presence of two rectangular masonry structures between the postholes on either side of the firebox.  These are called “vaults” and their function is unknown.  Some have proposed that they were footdrums, with boards laid over them and people dancing on top to provide percussion for the events in the kiva; others have proposed other functions, such as sweatlodges, places for germinating seeds or beans (which is something the Hopis do in their kivas today), etc.  In any case, another very standard feature of the Chacoan great kiva design, which is an indication of the amount of thought and planning that went into the elaborate region-wide Chacoan system, whatever it was.

Wall Dividing East and West Plazas, Pueblo Bonito

Turning from Kiva Q to the plaza, it becomes apparent that there are actually two plazas, separated by a block of rooms.  Moving south along the wall of this block of rooms, one comes to another block of rooms, enclosing the plazas on the south side and forming the straight side of the famous D-shape.  Where these two blocks of rooms intersect, there is a doorway.

Entrance to Pueblo Bonito

At the time this part of the building was completed, sometime in the early 1100s, this doorway was the only entrance to the building.  To get to any of the interior rooms, you would have had to enter here, go across the plaza, possibly go across the other plaza, then make your way through a maze of interconnected rooms.  It was not easy to get to many parts of this building.  Clearly an attempt to limit access, but why?  The early excavators assumed features like this were defensive in nature, but research has actually shown that there is very little evidence of warfare during the Chacoan era.  Indeed, it seems to have been a very peaceful time, particularly in comparison to the eras before and after it.  So probably not defensive, but still limited access, and the reasons for that are answered in different ways by the different theories about the function(s) of the great houses and the nature of the Chacoan system.

Wall Enclosing the West Plaza, Pueblo Bonito

There is, however, something else meaningful about this particular spot.  The aforementioned wall dividing the two plazas runs due north-south, within a degree of true north, and the wall enclosing the west plaza runs due east-west, again within a degree, and they come together in a 90-degree angle right here at the only entrance to the building.  This is clear evidence that, at least at this late date in the history of Pueblo Bonito, alignments were very important elements of the Chacoan architectural style.  This is a particularly clear example of cardinal direction alignments; there are also astronomical alignments at many buildings, as well as alignments between buildings.  This, along with the roads, the line-of-site communication network, and the various other landscaping and engineering projects throughout the Chacoan world, shows that the Chacoan system of architecture didn’t end at the walls of the building or even at the walls of the canyon.  Rather, it extended out, through roads and other networks to the surrounding region, and through abstract alignments to the cosmos itself and the movements of the sun and moon.  A very sophistocated and impressive system indeed.

A system this elaborate obviously required a lot of work to build and maintain.  From the impressive remains of it, it is clear that this work was done, and it seems like there must have been something, some idea or system of ideas, that was powerful enough to inspire someone to either do this work or get other people to do it.  Though we see some tantalizing glimpses and possibilities in the architecture and other remnants, ultimately we don’t know what that idea was.  We can’t see just what it was that inspired the creation of all this magnificent construction and design that, in turn, inspires us today.  There are theories, but none of them can really claim to have the whole answer, at least not in a way that will be universally accepted.  There are still many things we don’t know and will never know about Chaco.

That’s not necessarily a bad thing.  In some ways it can be a benefit to not know and to be able to ponder, think, and consider the possibilities and limitations inherent in the human experience, and I think Chaco offers that opportunity and that, to us today, that is a key (and, in any case, necessary) aspect of how we approach Chaco Canyon and Pueblo Bonito at the heart of it.  It’s a place of majesty and a place of mystery.

Obligatory Shot of Aligned Doorways at Pueblo Bonito

Read Full Post »