Spruce Tree House cliff dwellings. Mesa Verde National Park, photo taken by me May 2004.
No machine-readable author provided. <a href="//commons.wikimedia.org/wiki/User:Nebular110" title="User:Nebular110">Nebular110</a> assumed (based on copyright claims).
CC BY 2.5
No machine-readable source provided. Own work assumed (based on copyright claims).