The Hopi Reservation, or simply Hopi, is a Native American reservation for the Hopi and Arizona Tewa people, surrounded entirely by the Navajo Nation, in Navajo and Coconino counties of Arizona, USA. The site in north-eastern Arizona has a land area of 2,531.773 sq mi (6,557.262 km²) and as of the 2000 census had a population of 6,946. The Hopi Reservation, like most of Arizona but unlike the surrounding Navajo Nation, does not observe Daylight Saving Time. Until recently, the two nations shared the Navajo-Hopi Joint Use Area. The partition of this area, commonly known as Big Mountain, by Acts of Congress in 1974 and 1996, has resulted in continuing controversy.