According to the Korea Times, there are one million landmines hidden inside the DMZ. They were installed during the Korean War, between 1950-1953. In 2018, efforts began to remove landmines from both sides of the DMZ. While there have been a few accidents, mainly in the areas outside of the DMZ, you don’t need to worry about your visit. The entire region of the Korean Demilitarized Zone has been secured and is safe for tourism.