Around A.D. 800 life at Chaco Canyon started evolving into what would become a flourishing sociopolitical center for trade and ceremonial activities spanning over 300 years. “The Bonito Phase (ca. AD 850 to 1140) in Chaco Canyon,
New Mexico, is widely assumed by archeologists to reflect the growth and decline of a coherent sociopolitical entity…” (Wills 283) The central sites at Chaco are large, multi-story, planned structures incorporating advanced masonry techniques for the time. “From approximately A.D. 900 to 1130, the Chacoan society, a prehistoric
Pueblo culture, constructed numerous multistoried buildings and extensive roads throughout the eighty thousand square kilometers of the arid San Juan Basin of northwestern New Mexico (Cordell 1984; Lekson et al. 1988; Marshall et al. 1979;
Vivian 1990) Recent evidence suggests that expressions of the Chacoan culture extended over a region two to four times the size of the San Juan Basin (Fowler and
Stein 1992; Lekson et al. 1988). Chaco Canyon, where most of the largest buildings were constructed, was the center of the culture. The canyon is located close to the center of the high desert of the San Juan Basin.” (
Sofaer
) During the Bonito Phase the construction and expansion of the Puebloan peoples in Chaco Canyon was unsurpassed by any other period. “By 1050, Chaco had become the ceremonial, administrative, and economic center of the San Juan Basin. Its sphere of influence was extensive. Dozens of great houses in Chaco Canyon were connected by roads to more than 150 great houses throughout the region.” (NPS) There is substantial archaeological evidence pointing to the fact that Chaco Canyon was a sociopolitical center for the Puebloan peoples living in the San Juan Basin from the beginning of the 9 th century throughout the late 11 th century. “The widely held view of modern archaeologists is that Chaco served as a ritual or sacred center for communal activities by and for a regional population of Puebloan people. Evidence for this derives from studies of architecture, artifacts, burials, spatial associations, and specialized features, such as roads or pathways.” (Ritterbush) The sophisticated architecture in the canyon, roads leading to the canyon and presence and processing of rare materials in the canyon indicate that Chaco Canyon was a significant sociopolitical center in the southwest.

The architecture in Chaco Canyon exhibits significant advancement in planning and construction techniques compared to the precursor pit house traditions. “Astronomy played an important role in the Chaco culture. This is expressed in the cardinal alignments of the major axes of several large ceremonial structures at or near the center of the canyon and in a complex set of solar and lunar markings on Fajada Butte, at the south entrance of the canyon.”(Sofaer) The vast construction of Great Houses at Chaco occurred over many decades and in some cases centuries. “During the middle and late 800s, the great houses of Pueblo Bonito,
Una Vida, and Peñasco Blanco were constructed, followed by Hungo Pavi, Chetro
Ketl, Pueblo Alto, and others. Pueblo Bonito is the most elaborate example of architecture built by the Chacoan peoples. It is a massive great house consisting of almost 700 rooms. “These structures were often oriented to solar, lunar, and cardinal directions.” (NPS)
Pueblo Bonito is no exception. “An impressive feature of Pueblo Bonito is its alignment to the cardinal directions. A line drawn through the center of the half moon shape forms a precise north-south axis and the eastern-half of its southern wall is aligned east-west. On the spring and fall equinoxes, the Sun rises and sets in perfect alignment with this wall.” (Traditions) Dr. Shelley Valdez, a modern member of the Pueblo Laguna Tribe provided some explanation on the significance of the cardinal directions to modern Pueblo peoples: "(They) connect people, the seasons, the Sun and Moon's patterns, time, nature, the environment, the cosmos, and ceremonial systems. Observance of the cardinal directions and the Sun essentially ensured life by knowing when it was time to plant, harvest, and hunt for example.
Pueblo Bonito is a physical manifestation of these ideas."
The alignment of the architecture in Chaco Canyon with cosmic events indicates significance in their construction. “It is thought that the great houses were not traditional farming villages occupied by large populations. They may instead have been impressive examples of "public architecture" that were used periodically during times of ceremony, commerce, and trading when temporary populations came to the canyon for these events.” (NPS) The great houses often had several

hundred rooms including subterranean rooms called kivas; which were most likely used for ceremonial practices. “The great kivas and numerous smaller kivas clustered in the great houses were clearly centers of ritual and ceremony, as analogy with modern and historic Puebloan use of kivas shows.” (Ritterbush) In addition to kivas there is evidence of other specific architecture around the great houses that indicates non-traditional use of the area. “Sophisticated astronomical markers, communication features, water control devices, and formal earthen mounds surrounded them.” (NPS) The great houses in and around the canyon are exceptionally preserved examples of architectural evidence indicating that Chaco was a sociopolitical center.
Archaeological Evidence indicates that “In the late florescence of the Chaco civilization (c. AD 1050 to 1125) elaborate, formalized roads were constructed. No archetype for these roads appears to have existed in the region before their development by the Chacoans, and a recent inventory shows they were not used after the Chaco civilization's peak, about AD 1140.” (Sofaer) The presence of ancient roads leading into the canyon and converging on the central location of Pueblo
Bonito is evidence that Chaco Canyon was a significant destination for Chacoan peoples. “Approximately 300km of roads, including the Great North Road, have been documented in the last 15 years by aerial photography and ground investigation in numerous intensive studies.” (Sofaer) There are several intriguing aspects of the
Chaco roads most notably their construction and alignment. “The Chaco roads have been noted for their great width and unusual linearity, and they have been described as 'extensively engineered'. The roads were developed by excavation to a smooth, level surface, and some included masonry construction.” (Sofaer) Several of the Chacoan roads are aligned with the cardinal directions including “The Great
North Road.”
The Great North Road is a series of road segments that are aligned almost directly with true north. “The Great North Road (Figure 29.3) has its origin in several routes which ascend by staircases carved into the cliff from Pueblo Bonito and Chetro Ketl in Chaco Canyon, which are the two largest structures of the Chaco

region. These routes converge at Pueblo Alto, a large structure located close to the north rim of the canyon. From there the road runs 13 degrees to the east of north for
3 km to Escavada Wash. It then heads within 1/2 percent of true north for 16km, where it articulates with Pierre's Complex, an unusual cluster of small buildings on knobs and pinnacles. The road then heads close to 2 degrees east of north for 31 km and ends at Kutz Canyon.” (Sofaer) One of the most interesting features of the roads is the presence of staircases leading up and over large earth formations. Some of the staircases are very elaborate in construction with masonry techniques included in their formation. “Near the large community buildings of the canyon, several stairways were sculpted and large ramps were constructed. Several of the multiple roadways connecting these stairways and ramps with Pueblo Alto were curbed with masonry.” (Sofaer) The most elaborate of all the stairways is the one leading down into Kutz Canyon which “was built as a series of platforms which were supported by juniper posts and crossbeams and packed with earth (Marshall and Sofaer, 1988)
The road is believed to have been created primarily for ceremonial use in pilgrimages to sacred locations to the Chacoans. At 9m wide it is wider than would have been necessary for any applications at the time. “Considered from a utilitarian perspective, however, the road appears to be overbuilt and underused.” (Sofaer)
These factors all indicate that Chaco Canyon was a special sociopolitical and ceremonial center.
““Central place” pueblos in Chaco Canyon processed imported turquoise for economic exchange and ritual use. As ritual importance increased, residents of central places assumed greater ceremonial and managerial roles in alliance networks that expanded throughout the San Juan Basin, and Chaco Canyon became a center for ritual pilgrimages from outlier communities, with Chacoan roads serving as “conduits” to the canyon.” (Judge) There is substantial evidence indicating that during the period of the rise and fall of the Chacoan people extensive trade networks existed. “Quantities of ceramics, chipped stone, and timber were imported from areas 50-75 km to the south and west; tens of thousands of pieces of turquoise were recovered at Chaco although the nearest turquoise source is 200 km to the

east; copper bells and macaws were imported from Mesoamerica, and shell was imported from the Pacific coast.” (Cameron 2001: 10)
Chaco Canyon was a sociopolitical center with a heavy presence of ceremonial activities and trade taking place from around A.D. 800-1200. The
Chacoan peoples were very adept astronomers and could calculate various cosmological events. They used their knowledge of astronomy to find true north and align their buildings to the cardinal directions as well as calculate solar and lunar equinoxes and incorporate these events into their architectural angles. The presence of roads indicates a possible ceremonial pilgrimage route as they do not appear to have any practical function as well as lack of signs of use. Numerous artifacts have been unearthed in Chaco Canyon that indicate the presence of trade networks stretching as far as Mexico.