Mark Lawrence Bosworth, a mapping specialist for the Portland Metro, was last seen on September 16, 2011 at a Cycle Oregon event in Riddle, Oregon. He had been working at the booth near Riddle High School and was last seen walking along a road between Riddle and Canyonville, Oregon between 11:00 and 11:30 p.m. He had said he was going to find his tent, but he never arrived there and has never been heard from again. He was carrying less than $100 in cash on him when he vanished, probably about $40, as well as an iPhone 4 with a dead battery and possibly a small black bag with straps. He left his bicycle, wallet, credit cards and identification behind.

His case remains unsolved.