Reinhard Kirchner, a 61-year-old physicist from Germany, vanished while hiking in a remote part of the Navajo Reservation in Coconino County, Arizona, in early April 2007. He was an experienced, physically fit hiker who loved the Colorado Plateau and was carrying a day pack, a walking stick and a camera in a black case. He was reportedly wearing earth-toned hiking pants and a green or tan shirt.

The alarm was raised when he failed to meet his girlfriend in Las Vegas on April 9, 2007. An official search began April 12, 2007, after his rental truck was found near the rim of the Little Colorado River Gorge, west of Tuba City and about two miles from Hell Hole Bend. Search teams covered roughly 56 square miles of rugged terrain for six days but turned up no trace. Numerous sinkholes in the area were too dangerous for direct entry and were inspected with cameras instead.

No physical evidence connected to Kirchner has ever been found. The prevailing theory in the case is that he became lost or injured in the wilderness, but the lack of a clear direction of travel has frustrated investigators and family alike. Anyone with information about Kirchner’s disappearance is asked to contact the Coconino County Sheriff’s Office.