The Painted Desert is in the Four Corners area running from near the east end of the Grand Canyon National Park southeast into the Petrified Forest National Park. The Painted Desert encompasses over 93,500 acres and stretches over 160 miles. The Chinle Formation was deposited over 200 million years ago during the Late Triassic Period. The colorful badland hills, flat-topped mesas, and sculptured buttes of the Painted Desert are primarily made up of the Chinle Formation, mainly river related deposits.