A limestone wonderland of water and subterranean secrets.

This bridge made famous in a novel and on-screen wasn't actually built over the river Kwai.

A shrine built to combat the bad karma of a commercial venture.

Monkeys lounge around at this 13th century temple.

One man's swirling six-acre monument of stone.

Why have you never heard of the second most popular tourist site in New York?

This eccentric cave dwelling is bizarre even by the standards of a subterranean town.

An opal mining town in the middle of Australia where people live, worship, and shop underground.

One of the largest collections of traditional Māori artifacts in New Zealand.

Highly spherical boulders on the shores of New Zealand.

Major tourist destination known for its bubbling mud-pools and hot thermal springs.

A perfect turquoise lake colored with glacier dust.

This electric green sulphur lake in New Zealand looks like a cartoonish radioactive dump site.

Dolphins, ancient clams and hundreds of waterfalls make this one of the world's top tourist destinations.

A small museum in the Bay of Pigs gives the Cuban perspective on the famously failed U.S. invasion.

Prehistoric history as seen through the lens of an outsider artist.

An old slave lookout in Cuba's historic sugar cane fields.

Castro's communist ice cream mothership has been serving five-scoop "salads" for over 50 years.

After the Cuban Revolution, the famous rum company had to leave their swanky headquarters behind.

This imposing memorial contains the remains of Che Guevara — and 29 other guerrillas who died with him in Bolivia.

Once a favorite playground for the world's most illustrious guests, Hotel Nacional's secret weapons and bunkers reveal a more menacing side to its golden history.

A focal point of the Cuban government, this city square features one of the most iconic images in the country.

A nuclear power plant abandoned along with an international allegience.

In terms of history and architecture, this is one of the most remarkable cemeteries in the world.