An eerie, derelict amusement park in Berlin.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

One of the greatest maze designer’s greatest mazes.

Rent out a glass igloo to watch the Northern Lights like you live in the future.

A 19th-century subterranean reservoir repurposed as a contemporary art cave.

Vortex-shaped aquarium hosts Europe's largest school of piranhas and other ocean creatures.

An old asylum graveyard that's been abandoned for half a century attracts those seeking a dark thrill.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

The vast chamber inside this abandoned cooling tower looks like something out of a sci-fi dystopia.

Each spring, a dreamlike carpet of bluebells overtakes the forest floor.

A naturally beautiful, seemingly bottomless deep blue spring.

This scalding hot river was thought to be a myth until one geoscientist made it his quest to study the mystical waters.

An explosion of natural color known as "the river that ran away from paradise."

A record-breaking pool that uses computers to turn ocean water into cleaner, private swimming water.

This Japanese-inspired labyrinth of hot springs is hidden in a Chilean forest.

This odd Chilean waterfall-cano hotel must be entered via a rope bridge.

The haunting peak of an old church is all that remains of a drowned Brazilian city.

A small but industrious mining operation that allows visitors to touch precious gems while they are still in the rock.

You may get stranded and everyone's peeing in the water, but at least there's cocktails!

Cavernous opening completely encased in Karst limestone.

An island filled with hundreds of hanging, decomposing, decapitated dolls.

A gargantuan crystal kingdom.

Volcanically heated hot springs.

Hidden deep in the Guatemalan jungle is a turquoise paradise of natural pools, caves, and waterfalls.