South Korea's largely symbolic, barely used gateway to the North.

A large visitor's complex and place of remembrance on the outskirts of the DMZ.

The site of many tense prisoner exchanges across the Military Demarcation Line between North and South Korea.

The best place for scenic views of the DMZ and North Korea.

A one-of-a-kind sundial at the Very Large Array honors a radio astronomy pioneer, incorporating the original piers from his breakthrough radio telescope.

Seemingly grown on some other world, these New Mexico rock formations look like a disused science fiction set.

Albuquerque found the perfect use for tumbleweeds at Christmastime.

Limestone caves with spectacular showcase chambers.

Preserving the remains of Native American cultures which otherwise would have been submerged behind Hoover Dam.

A Bulgarian monument to Russia's role in World War II is constantly being painted in pop culture protest.

A castle built for love, and abandoned due to heartbreak.

The oldest Christian monastery in Iraq until ISIS blew it up twice and then drove over it with bulldozers.

The most playful of the life-sized statues that make up Singapore's "People of the River."

Teeming with illegal goods and services, this towering maze of vice is also a popular tourist accommodation.

Home to more than 13,000 pieces of war memorabilia and military equipment.

A wild west cemetery in Tombstone, Arizona, provides a window into the Old West.

The world's largest rose bush has literally outgrown the pioneer museum it was planted behind.

An old saloon in the West filled with history, and according to some, a few dozen ghosts.

Watch the newest land on the planet form before your eyes.

This ancient Hawaiian henge may have been an early star chart.

The world's longest outdoor covered escalator system transports commuters through Hong Kong's hilly terrain.

Secret North Korean passage discovered below the world's most dangerous border.

Twenty-seven massive radio antennas on the high plains of New Mexico search for life on other planets.

"I did this all while you were watching TV."