Although I was at the DMZ constantly during my two tours in Korea, I only visited Panmunjom (PMJ) once. Had to dress up in greens and couldn't wear my military intelligence brass on my uniform (had to borrow the eagles of the general staff from someone in my barracks). A very surreal place. Can truthfully say I've been to DPRK/north Korea, as PMJ is in both Koreas. When we were at the DMZ on duty, we wore MP (military police)brassards, as UN troops and north Koreans jointly patrol the area under the cease fire from 1953.
I had the good fortune of researching in the field at Bonifas with the Battalion Scouts (In Front of Them All!)