TOPSHOT - South Korean soldiers open the gate as the rails which leads to North Korea is seen, inside the demilitarized zone separating the two Koreas in Paju on November 30, 2018. - A train carrying South Korean engineers and officials crossed the border into North Korea for a joint survey with North Koreans for reconnecting the two Koreas with railways. (Photo by KIM HONG-JI / POOL / AFP)