Stone Circles of Chaco Canyon, Northwestern New Mexico

In the summer of l972, the Chaco Center, a research facility of the National Park Service and the University of New Mexico, implemented a proposal to intensively survey the 32 square miles composing Chaco Canyon National Monument. During the course of this survey a number of unusual sites for which there had been little previous documentation were recorded. A limited number of these sites were later classified as shrines belonging to a visual-communications network, skillfully placed to link ceremonial features and the large Bonito Phase ruins (Hayes and Windes l975). The others did not fall into the shrine category, and were listed instead as "stonecircles" (Fig. l).

The most distinctive feature of these sites was an oval or circular wall enclosing an area 9-32 m across the long axis and 7-20 m across the short axis. Circular, or rarely rectangular, basins were commonly observed to be set in the bedrock within the encircling wall. All of the circles were built upon bedrock along the high cliff-edges that border and overlook Chaco Canyon (Figs. 2-5). Judd (l964:l4l) briefly mentioned the existence of one such circle behind Pueblo Bonito. Snyder (l947:l0-l2) and R. Gwinn Vivian (l970a:l98-l99) observed a group of such circles near Pueblo Alto, and attributed a water-collection or water-retardation function to them.

In the summer of l974, the author, under the direction of Alden C. Hayes, undertook the task of finding out more about the circles and their relationship to the extensive Chacoan community. Despite the lack of artifacts found in these sites during survey, mapping and clearing of the sandy overburden from a few of the better preserved circles was expected to greatly expand our knowledge of these strange structures about which we knew so little. Specifically, we were interested in determining the distribution, cultural affiliation (Anasazi or Navajo), age, function, and attributes of the stonecircles. Initially, all circles were to be mapped with plane table and alidade, but the discovery of more stonecircles during the summer prevented the completion of this project. Of the 20 known circles, 19 were mapped. Due to time limitations, only two sites (consisting of seven circles and a possible garden plot) were cleared of most of the sandy fill that partially buried them.