Monument Valley (Navajo: Tsé Biiʼ Ndzisgaii, meaning valley of the rocks) is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching 1,000 ft (300 m) above the valley floor. It is located on the northern border of Arizona with southern Utah (around 36°59′N 110°6′W), near the Four Corners area. The valley lies within the range of the Navajo Nation Reservation, and is accessible from U.S. Highway 163.