According to Time, four tunnels from North Korea into South Korea have been discovered, most recently in 1990. The tunnels were capable of transferring up to 30,000 troops in an hour, the magazine reported.
The village of Panmunjom is located within the DMZ. It was the site of peace discussions during the Korea war and has been the site of several conferences through the years involving the two Koreas, Brittanica reported.
There have been incidents at the DMZ, most notably in January 1968, when a team of 31 North Korean commandos crossed the DMZ and attempted to assassinate South Korean President Park Chung-Hee, according to Time.