CHACO CANYON, NEW MEXICO

About AD 1000, Pueblo Bonito stood at the center of Chacoan culture in the arid region at the intersection of present-day Utah, Colorado, Arizona, and New Mexico. The largest site in Chaco Canyon, Pueblo Bonito originally stood four or five stories tall and housed more than 600 rooms, including 35 kivas, the circular structures visible around the perimeter of the large plazas. Chaco residents covered each kiva with a roof, creating a darkened underground space for ceremonial rituals. Why might these spaces be built below ground and separated from the other rooms of the pueblo?