"This is still a very volatile area," a United States Military official says. "We're within range of artillery and a nuclear threat."

It's a line that's divided countries and families for 65 years. A place established by war and protected by fear.

The Demilitarized Zone is a buffer between North and South Korea—two and a half miles wide and 160 miles long. Although the zone is demilitarized, it's the most fortified border in the world, heavily guarded on both sides with armed soldiers on patrol and attack helicopters flying overhead.

Under military escort, we enter the joint security area—the only portion of the DMZ where North and South Koreans stare face to face, always wearing sunglasses

In the past, even an unintended glance has caused conflict.

Directly on the border is the military armistice commission, where the North and South still hold talks, a table splitting the room and the two countries.

"Hands down the most volatile area," the official repeats. "They [North Korea] can hear what you're saying right now."

This is a view very few people get to see, the seemingly serene terrain in a place of high tension watched day and night by two countries on edge.

You also see the bridge of no return, where nearly 96 thousand prisoners of war were exchanged at the end of the Korean War.

A war that may have actually never ended.