- The Demilitarized Zone, where President Donald Trump met North Korean leader Kim Jong Un on Sunday, may be the most heavily fortified strip of land in the world.
- There isn't much demilitarized about it: A minefield laced with barbed wire, it's guarded by combat-ready troops on both sides and has been the site of numerous, sometimes deadly gunbattles and skirmishes.
- The venue of the third Trump-Kim meeting was the Korean border village of Panmunjom, located inside the DMZ.
- Trump became the first sitting U.S. president to set foot in North Korea when he crossed over the military demarcation line in the village into the North before he turned back to the southern side together with Kim.
The Demilitarized Zone, where President Donald Trump met North Korean leader Kim Jong Un on Sunday, may be the most heavily fortified strip of land in the world and serves as an uneasy and occasionally bloody borderline between the two Koreas.
There isn't much demilitarized about it: A minefield laced with barbed wire, it's guarded by combat-ready troops on both sides and has been the site of numerous, sometimes deadly gunbattles and skirmishes. U.S. presidents and other top officials have often traveled to the DMZ to reaffirm their commitment to the defense of ally South Korea in times of hostility with North Korea.
The venue of the third Trump-Kim meeting was the Korean border village of Panmunjom, located inside the DMZ. Trump became the first sitting U.S. president to set foot in North Korea when he crossed over the military demarcation line in the village into the North before he turned back to the southern side together with Kim for their third summit.
The DMZ, which runs across the Korean Peninsula, is 248 kilometers (154 miles) long and 4 kilometers (2.5 miles) wide. Created as a buffer at the close of the 1950-53 Korean War, it's jointly overseen by the American-led U.N. Command and North Korea.
Hundreds of thousands of North and South Korean troops are now deployed along the DMZ, which is littered with an estimated 2 million mines, tank traps, razor wire fences and guard posts.
It's extremely rare for anyone to cross the DMZ in unauthorized areas. More than 30,000 North Koreans have escaped to South Korea for political and economic reasons since the war's end, but mostly via the North's long, porous border with China.
Violence was more common in the Cold War, but a 2015 land mine blast blamed on North Korea maimed two South Korean soldiers and pushed the rival Koreas to the brink of an armed conflict.
As relations improved last year, the two Koreas agreed on several deals aimed at reducing animosity at the border. They removed mines from certain areas, dismantled some of their guard posts and halted front-line live-fire exercises. Experts say tensions can easily return if diplomacy eventually fails to end the North Korean nuclear stalemate.
Panmunjom has been the venue for past high-level talks. It's somewhat safer than other areas, and it is just an hour's drive from Seoul, South Korea's capital. Most past DMZ visits by U.S. presidents and other officials happened at Panmunjom and nearby areas.
Sunday's summit between Trump and Kim took place in a building in the southern part of Panmunjom. Before the meeting, Trump and Kim shook hands and posed for photos several times as they stepped across the concrete slabs that form the village's borderline.
Last year, Kim came to the village's southern side when he held a summit with South Korean President Moon Jae-in, becoming the first North Korean leader to set foot in the South.
North and South Korean troops stand only several meters (yards) away from each other there. They once carried pistols, but since last year's deals they aren't armed.
Panmunjom is also where an armistice was signed to stop the Korean War. That armistice has yet to be replaced with a peace treaty, leaving the Korean Peninsula in a technical state of war. About 28,500 American troops are still stationed in South Korea.
Panmunjom is 52 kilometers (32 miles) north of Seoul and 147 kilometers (91 miles) south of Pyongyang, North Korea's capital.
Since the armistice, more than 830 rounds of talks have been held in various Panmunjom conference rooms.
The most notorious incident at Panmunjom happened in 1976, when ax-wielding North Korean soldiers killed two U.S. officers sent out to trim a tree that obstructed the view from a checkpoint. Washington sent nuclear-capable bombers toward the DMZ in response. Animosities eased after North Korea's then-leader, Kim Il Sung, the grandfather of Kim Jong Un, expressed regret over the incident.
In 2017, North Korean soldiers sprayed bullets at a colleague who was making a dash for the border. He survived and now lives in South Korea.
In 1993, President Bill Clinton visited Panmunjom when the North Korean nuclear crisis first flared. In 2002, President George W. Bush visited the DMZ a few weeks after he labeled North Korea part of an "axis of evil."
In March 2012, Kim Jong Un came down to Panmunjom and met front-line North Korean troops in his first known visit to the area since taking power in late 2011. He gave the troops rifles and machine guns as souvenirs and ordered them to maintain "maximum alertness," according to North Korean state media.
Days after Kim's Panmunjom trip and ahead of a planned North Korean long-range rocket launch, President Barack Obama visited a front-line U.S. military camp just south of the DMZ and told American troops they are protectors of "freedom's frontier."
In November 2017, Trump planned to visit the DMZ with Moon to underscore his stance on North Korea's nuclear program, but his plans were thwarted by heavy fog that prevented his helicopter from landing at the border.