At about 7 am on 17 December 1943, during World War II, a United States Army Air Forces (USAAF) plane crashed into the northerly face of Cnoc na Péiste. The plane was a Douglas C-47 or Dakota (serial number 43-30719) with five crewmen aboard. It struck the mountain just above Lough Cummeenapeasta at an altitude of about 2,000 ft—killing all five passengers. The Gardaí were not alerted to the crash until 3 February 1944, and the following day an Irish Army detachment was sent to recover the bodies. Pieces of the aircraft can still be seen on the mountainside, and in the lake below (a rope is tied to a piece of the wreckage in the water). A plaque was placed at the shore of the lake to commemorate the victims.