The Colorado Plateau is a physiographic region of southwestern North America. It covers some 388,500 km² (150,000 sq miles) of Arizona, Utah, Colorado and New Mexico, including the 'Four Corners' area. It is characterized by broad plateaus, ancient volcanic mountains at elevations of 1,520 to 3,960 m (5,000-13,000 feet) and deeply dissected canyons that are lined with often brightly colored sedimentary and volcanic rocks, including the Grand Canyon of the Colorado River.

Native American reservations occupy about one third of the mostly semiarid and sparsely vegetated area, which was the last U.S. region to be explored by whites. About one half of the public land is used for grazing. Among many ancient cliff dwellings are those at Mesa Verde and Canyon de Chelly. The region has a number of U.S. national parks and monuments.