Other outstanding ruins in the monument are Wukoki ruin, another fortified apartment house; and Crack-in-the-Rock ruin near the Little Colorado River. To reach these more inaccessible ruins, it is necessary to make arrangements with the custodian in Wupatki ruin. Abandonment All of the ruins were abandoned in the 1200’s. This is accounted for, partly at least, by several factors—high winds sweeping the moisture-conserving cinder fields, climatic changes, and disease among the Indians. It brought to a close one of the unique chapters of Southwestern archeology. Probably among the present day Hopis the descendants of these people are to be found. Drought and disease, possibly also attacks of nomad enemies, caused the abandonment by the Pueblos of most of northern Arizona during the thirteenth century. This region, the Tsegi region (Navajo National Monument and vicinity), and the region of Canyon de Chelly National Monument were deserted. The survivors from all these areas must have congregated at the Hopi mesas, where the springs never fail. Later, in the fourteenth century, the great pueblos of Chaves Pass and Homolovi (near Winslow, Ariz.) and of the Verde Valley (notably Tuzigoot and Montezuma Castle National Monuments) were abandoned, their people going northeast to swell the Hopi nation. When the Spaniards arrived in 1540 there were no pueblo villages occupied in Arizona save those of the Hopi, in Tusayan. [Illustration: The Citadel] Tree-Ring Dates The time of occupation of each ruin in this region is fairly well known, through the tree-ring method of dating prehistoric sites. The date of eruption of Sunset Crater is approximately known, from the dating by the tree-ring method of houses built before and after the cinder fall. Nearby Points of Interest By visiting Sunset Crater, Wupatki, and Walnut Canyon National Monuments, and also the Museum of Northern Arizona in Flagstaff, Ariz., visitors can obtain first-hand knowledge of one of the most interesting localities in the United States. The story of each area is linked with the others. The Museum of Northern Arizona has been instrumental in searching out the scientific facts concerning the manifestations of nature and man in the region and displays interesting exhibits which help to explain them. The exhibits to be installed by the National Park Service at Walnut Canyon and Wupatki will be specifically explanatory of the monuments; the Museum of Northern Arizona presents a picture of the entire region. How to Get to Wupatki