...Canyon de Chelly National Monument, a comparatively little-known canyon is not as immediately spectacular as others in Arizona or Utah but it does have sheer sandstone walls rising up to 1,000 feet, several scenic overlooks and many well-preserved Anasazi ruins, and the area provides a fascinating insight into the present day life of the Navajo, who still inhabit and cultivate the valley floor. The canyon floor remains green and fertile all year round; this, together with the protection offered by the rocky walls and the beauty of the landscape explain why the valley has been inhabited for so long - from primitive peoples 2,000 years ago, through the Anasazi civilisation of the twelfth century which occupied a large area of the Southwest before suddenly disappearing, to the Navajo who have lived here for the last 300 years. They rear sheep and goats in the canyon, and plant crops. (http://www.americansouthwest.net/arizona/canyon_de_chelly/national_monument.html)