The Korean War halted in 1953 with an armistice — but a formal peace treaty was never signed. As part of the armistice, the American-led United Nations Command and the Communist generals of North Korea and China agreed to create a two-and-a-half-mile-wide buffer zone that divides the Korean Peninsula to keep the warring armies apart.

Known as the DMZ, the buffer zone was supposed to be “demilitarized,” but soon became a heavily fortified frontier riddled with land mines and surrounded by fences and guard posts.

Then last year, South Korea’s president, Moon Jae-in, and North Korea’s leader, Kim Jong-un, took a symbolic step. Hand in hand, they crossed over the demarcation line, signifying what many hoped was the start of a new era.

The two leaders’ summit meeting itself offered little in the way of a concrete plan for peace, but the theater of the crossing resonated globally. Still, while a formal peace agreement may finally be in sight, the border remains heavily fortified.