Located on Navajo trust land and having a resident community, Canyon de Chelly National Monument is unique among national park units. The National Park Service, Navajo Nation, and canyon community work in conjunction to manage park resources and enable traditional and contemporary lifeways.  Canyon de Chelly National Monument preserves one of the longest, continually inhabited locations by American Indian communities in the United States, spanning at least 5,000 years. Tséyi’, the place within the rock, sustains a living community connected to a landscape of great historical and spiritual significance—a landscape composed of places infused with collective memory and defining moments in Navajo history. It is essential to the spiritual and traditional lives and cultural identity of many native peoples.  Encompassing 83,840 acres, Canyon de Chelly National Monument was authorized in 1931 by President Herbert Hoover in large measure to preserve the large concentration of archeological resources.