Mary Lucille Sloan, 53, was last seen at a remote campsite in the Columbine area of Mount Graham in early September 2015, with the last sighting believed to be the evening of September 1. She had been camping with seven other adults on an isolated Forest Service access road near Grandview Peak Road and Riggs Lake. The next morning she was gone; her tent contained her bedroll, food, purse, and cell phone and appeared unused, suggesting she had not slept there.

An initial search by her companions grew into a multi-agency operation. By September 4 a formal ground search was underway and the Arizona Department of Public Safety deployed a helicopter. Search teams from Maricopa, Cochise, Pima and Graham counties participated, using ground, canine and cadaver dog teams. One dog reportedly gave an alert near a steep cliff, prompting mountain rappelling teams, but no physical trace of Sloan was ever found and the official search was later suspended.

Reports note several possible explanations mentioned by investigators and family, including an accidental fall in the dark or the possibility she walked away after recent bereavement; the campsite’s isolation led some to view abduction as less likely but not ruled out. Does anyone who visited the Columbine area around that time or who knew Mary have information that could help explain what happened?