Tuesday, August 19, 2008

Great House Pueblo Trail at Chimney Rock

The Pueblo Trail is the highlight trail at the Chimney Rock Archaeological Area. The 1.0 mile round trip climbs upwards toward the Chimney Rocks and the large Great House that is oddly located in this high mesa area.

The Chimney Rock Archaeology Area is an unusual Chaco Canyon influenced site located between Bayfield and Pagosa Springs in southwest Colorado. There are two short trails on the tour of the Chimney Rock area. Visitors sign in at the small visitor center and caravan up a gravel road for two miles to the trail head area.

An interesting stop right at the bottom of the trail is the Ridge House. This three room site is thought to be a residence and it shows the thick walls that seem to be typical of most of the Chimney Rock sites. At most other sites in the Four Corners Area circular masonry structures are interpreted to be kivas and residence rooms are more rectangular. Here, the masonry residence rooms are circular.

The trail up to the Great House is narrow and a little exposed. On the east side the vegetation is Pinon Pine and Utah Juniper trees but on the west side there are taller Douglas Firs. One of the reasons that Chaco Canyon People might have needed to come here is for access to the forest resources, such as large trees.

That leaves aside the engineering problem of transporting these large trees 90 miles south to the desert area of Chaco Canyon. The nearby Piedra River may have offered a way to float the trees part of the way. Then they would have to have been rolled or carried. No beasts of burden were available to the Ancestral Pueblo people.

The Great House shows all the features of a Chaco Canyon style structure. It is thought to have been used more for storage, or maybe festivals rather than residence, and is thought to have mostly been built all at one time, rather than been enlarged gradually as a growing village would require.

It is built in straight lines, the thick walls have an interior of rubble and nicely placed veneer exterior stones that show signs of having been shaped for a flat exterior finish. Tiny slabs of sandstone are inserted between the larger bricks as a type on chinking. This seems to be a typical feature of Chaco style building. This wall is the outside of the large circular kiva.

From the Great House area there is a birds eye view of the Chimney rocks. One of the reasons that the Great House might have been built in this difficult location is for festivals and ceremonies involving observation of the moon and sun as they rise between the notch formed by these rocks. An excess of grinding stones were found on the Great House, and this is interpreted as something like a hotel room equipped with cooking gear.

The first stage of construction is thought to have been around 1076 AD and the entire site is thought to have been abandoned by 1125 AD, so this building seems to have been used for only about 50 years. It looks like we are seeing about 40 percent of the original floor plan of the building. These rooms on the north side are had an exterior door and an interior door to the inner room, and both rooms had a second story room reached by a ladder.

The south side of the Great House is dominated by the two kivas, though only one is easily visible. The total tour at Chimney Rock takes about 2.5 hours. The hike is not long but the climb may tax those not used to hiking. Most of the time is spent viewing these ancient structures.

The interpretation of the Great House seems to hinge on the two rocks that seem to form a gunsight for observations of the sun and moon. Quite a bit of effort has gone into establishing that during a "lunar standstill" the moon could be observed rising right between the two rock spires. A lunar standstill is a period that occurs every 18.6 years when the moon rises at a maximum northerly position and the change in its path from maximum high in the sky to minimum low on the horizon occurs in a two week period. In other years in the cycle, the variation in path is barely noticeable. This apparently carried enough significance that they went to great effort to view it from a prime spot. The last lunar standstill was in 2006.

Another puzzle about the Chimney Rock area is that the food production appears to have mostly been in the Piedra River valley below. It was quite a distance from the high mesa area down to the river. These sites are thought to have been abandoned in 1125 AD, which is earlier than the around 1300 AD dates often given for the regionally nearby Mesa Verde sites. There is no evidence that Chimney Rock was reoccupied as some of the other Chaco influenced sites were. So the mystery here is deeper. Why abandoned so early and why did it stay abandoned.




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