Haunted Prisons - SCI Pittsburgh
(Pittsburgh PA, USA)
When I worked there in 2001, I saw the ghost of a guard who was shot and killed in a riot at that same prison in 1925. This guard appeared to me on a tower post on the wall. He was in uniform. I could see his whole body, but his eyes were closed. It started to rain and the rain outlined his body so a could see him better. This was at 1130 am.
When I opened the tower door, he was gone.