Canyonland Grotto, Utah

Photograph by Walter Meayers Edwards

A vaulted grotto with a skylight shelters the ruins of cliff dwellings. The Anasazi, or Ancient Ones, tilled corn in the valley below and retreated to the heights at night. Whether fleeing enemies or a prolonged and widespread drought, they disappeared from Utah by about 1300. This canyon, near Salt Creek in Utah's Canyonlands National Park, also shows evidence of disastrous flash floods at that time. Visitors today know the huge alcove as Paul Bunyan's Potty.

(Photo shot on assignment for "Canyonlands, Realm of Rock and the Far Horizon," July 1971, National Geographic magazine)