This doorway to the past is part of a the cliff dwelling at Palatki Heritage Site in Sedona, AZ. The archeological site, part of the Coconino National Forest, is set among the famous red rocks the area is famous for. The Sinagua people are believed to have lived in these stone structures, built into the rocks, from 1150 to 1300 AD. If you want to visit, make reservations. They are required here due to high demand and limited parking. Another way to view them is via jeep tours, a popular activity in the area.