The headquarters of the Mahanikai school of Buddhism, Thailand's largest monastic order.

A limestone wonderland of water and subterranean secrets.

The world's most remote airport.

This was once the center of the Birdman cult, and is now a World Heritage Site.

The largest stone moai on Rapa Nui.

Known as the Sistine Chapel of Egypt, this tomb houses some of the most well-preserved paintings in Egypt.

This ancient structure is widely thought to be the oldest intact pyramid in the world.

These Egyptian statues have survived for 3,400 years and were an acoustic wonder of the ancient world.

This small monument marks the divide between the Atlantic and Indian Oceans at the southernmost tip of Africa.

Formerly known as the Malay Quarter, Bo Kaap is a colorfully-painted suburb located in the “Mother City” of South Africa.

This African beach is home to thousands of rare mainland penguins that are known for their annoying voice.

Raging waters have created a strange geological site that looks like something off of a progressive rock album cover.

An eerie, derelict amusement park in Berlin.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

This abandoned Slovenian military barracks has become a punky-political art squat.

A whimsical bridge adorned with decorative dragons.

This one-time health resort was used by aristocrats around the world.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

Climb inside an iron crystal magnified 165 billion times its normal size.

Cozy basement bar sports an inventory of over 2,000 beers.

A little sculpture with a large wardrobe.

Carvings in Turkey's Marble Road may have directed ancient Romans to a hidden brothel.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

Roman ruins top white travertine terraces formed by ancient hot springs.