The horizon is awash in color for but a few minutes after the sun sets in the Painted Desert, Arizona. The Painted Desert encompasses over 93,500 acres, stretching for over 160 miles, and derives its name for the multitude of colors ranging from lavenders to shades of gray with vibrant reds, oranges and pink – colors observed here in the evening clouds. The area is a long expanse of badland hills and buttes which, although barren and austere, encompass a rainbow of colors due to the colorful sediments of bentonite clay and sandstone.
The desert is composed of stratified layers of easily erodible siltstone, mudstone, and shale of the Triassic Chinle Formation. These fine-grained rock layers contain abundant iron and manganese compounds which provide the pigments for the various colors of the region.
The Painted Desert was named by an expedition under Francisco Vázquez de Coronado on his 1540 quest to find the Seven Cities of Cibola, which he located some forty miles east of here. Discovering that the cities were not made of gold, Coronado sent an expedition to find the Colorado River for supplies. The group passed through the colorful landscape and named the area "El Desierto Pintado" - The Painted Desert.