Sometime between 1046 and 1070 A.D., probably in 1066, a volcano fifteen miles northeast of the present town of Flagstaff erupted. This volcano, now known as Sunset Crater, covered some 800 square miles with a black ash, and forced the early inhabitants to flee from their homes on the lower slopes of the San Francisco Mountains. This seeming disaster, however, was really a very fortunate occurrence, for the fine black material strewn over the countryside by the volcano provided a mulch which aided in conserving moisture and made the practice of agriculture possible over a wider area. [Illustration: Fig. 58—Montezuma Castle National Monument, Arizona. (Courtesy National Park Service.)] Not only did the original Sinagua people return to the area, but Hohokam and Pueblo people moved in too, bringing with them their own special traits. The Hohokam introduced their type of architecture and their distinctive ball courts, and the Anasazi introduced the Pueblo architecture which was adopted by the Sinaguans. At first, masonry was used to replace timbers in pit houses, but in a very short time the Sinagua people began building surface masonry dwellings and multi-roomed pueblos became the rule. During the years of the great drought of 1276 to 1299, many more people left the area and moved farther south into the Hohokam territory where some Sinaguans had already settled. Shortly after 1300 A.D. the Flagstaff area was abandoned. Some people stayed in the Verde Valley and built large pueblos. This southern branch is best known from the impressive sites of Tuzigoot[13] and Montezuma Castle, now National Monuments. Others may have gone farther south and mixed with the Hohokam in the Gila Basin, and some may have moved to the Little Colorado area and may be among the ancestors of the present Hopi Indians. CHAPTER VII THE PATAYAN CULTURE The prehistoric people who lived in the valley of the Colorado River below the Grand Canyon are the least well known in the Southwest, for most information about them has been derived only from surface surveys. Originally, the term _Yuman_ was applied to these people, for Indians speaking a Yuman language were found there by the first white men to visit the area.[35] Some archaeologists still use this term, and it is commonly applied to the culture found in the lower Colorado River basin and adjacent areas in California.[116] Others feel that it is unwise to apply a linguistic term to a prehistoric culture and use the term _Patayan_, a Walapai word meaning “the old people.”[16] It is postulated that the Patayan or Yuman is a basic culture or root to which should be given the same status as the Anasazi and Hohokam.