回复：从北韩那边也可以下隧道吗？

Certainly not. Usually the packaged tour to the North includes a day or so to Panmunjom and Kaesong. It was very interesting to see the same meeting room thru two opposite entrances - with a detour involving a 3rd country. Nowadays the soldier from either side steps out of the meeting room whenever the other side has a tour group.