Indian Ruins, San Juan County, New Mexico
In the cliffs behind the ruins there are ancient stairways that lead to prehistoric roadways that connect to Pueblo Bonito. Chetro Ketl consists of a large set of rooms in a rectangular configuration similar to late era Great Houses at Chaco such as Kin Kletso, and a long D-shaped wall which encloses a packed earth plaza. The site has many architectural elements that appear to reflect Mexican Toltec influence. Begun c.1020 AD, its 450–550 rooms shared a great kiva which is among the largest ever built in the American Southwest. Scientists estimate that it took 29,135 man-hours of construction to erect Chetro Ketl; Hewett estimated that it required the wood of 5,000 trees and 50 million stone blocks.