A thousand years ago, Chaco Canyon sat at the center of a thriving civilization. Ancestors of the Pueblo Indians built monumental “great houses” from the yellow-orange sandstone that permeates the region. The largest of the great houses is Pueblo Bonito. In its prime, this giant building was four stories tall and had more than 600 rooms.
Pueblo Bonito sits on the north rim of Chaco Canyon, the brown and white strip that runs diagonally across the center of this image, taken on September 7, 2004, by the Ikonos satellite. The pale brown ribbon of the Chaco River itself winds down the center of the canyon. Bluffs rise behind the D-shaped Pueblo Bonito, and lighter yellow grasslands top the plateau. Thin black roads leading to the Chaco Canyon sites line the canyon through the Chaco Canyon National Historical Park.
The half-moon-shaped Pueblo Bonito, shown in the inset, is perfectly aligned with the cardinal directions. The southern wall runs along the east-west axis and a perpendicular line drawn from the wall through the center of the curve would point directly north. In addition to having possible religious and cultural significance, this alignment would help people track the seasons, telling them when to plant and when to prepare for winter.