Monument Valley is a region of the Colorado Plateau characterized by a cluster of vast sandstone buttes, the largest reaching 1,000 ft above the valley floor. It is located on the Arizona-Utah border, near the Four Corners area. The valley lies within the territory of the Navajo Nation Reservation and is accessible from U.S. Highway 163. Monument Valley is officially a large area that includes much of the area surrounding Monument Valley Navajo Tribal Park, a Navajo Nation equivalent to a national park. Monument Valley has been featured in many forms of media since the 1930s. Director John Ford used the location for a number of his best-known films and thus, in the words of critic Keith Phipps, "its five square miles have defined what decades of moviegoers think of when they imagine the American West."-Wikipedia