Monument Valley (meaning valley of the rocks) is a region of the Colorado Plateau characterized by a cluster of sandstone buttes, the largest reaching 1,000 ft (300 m) above the valley floor.
The most famous butte formations are located in northeastern Arizona along the Utah-Arizona state line.
The valley is considered sacred by the Navajo Nation, the Native American people within whose reservation it lies.
The area is part of the Colorado Plateau.
The elevation of the valley floor ranges from 5,000 to 6,000 feet (1,500 to 1,800 m) above sea level.
The floor is largely siltstone of the Cutler Group, or sand derived from it, deposited by the meandering rivers that carved the valley.
The valley's vivid red color comes from iron oxide exposed in the weathered siltstone.
The darker, blue-gray rocks in the valley get their color from manganese oxide.
The buttes are clearly stratified, with three principal layers.
The lowest layer is the Organ Rock Shale, the middle is de Chelly Sandstone, and the top layer is the Moenkopi Formation capped by Shinarump Conglomerate.
The valley includes large stone structures, including the "Eye of the Sun".