Anasazi
The Chaco Anasazi of the northern Southwestern United States emerged as a unique tradition between approximately A.D. 900 and 1150. This cultural tradition is marked by a variety of distinctive features, of which their architecture is the most prominent. Not only did the Chaco Anasazi build the most impressive above-ground masonry structures found in North America, they also constructed large subterranean Great Kivas that could measure up to 30 m. across.
Anasazi	History, culture and quicktime movies
Anasazi: The Great Kiva	"Anasazi" is a Navajo word meaning "ancient ones." Archaeologists use it to describe the Basketmaker-Pueblo culture that existed from about A.D. 1 to 1300 in the Four Corners Plateau region of Colorado, New Mexico, Arizona and Utah.