Aerial Photo: Looking west down Alcove Canyon on the Navajo Reservation, Four Corners area. This is purported to be the 3rd longest deepest canyon in Arizona, after The Grand Canyon and Canyon de Chelly. It is accessed via Sweetwater or Cove, AZ. It is packed full of ancient sites of the: Archaic, Basketmaker and Anasazi paleolithic peoples. Shot from an Air-Cam aerial photography plane designed by the Nat. Geo. Society. Plane is at Cortez Colorado Airport.