This orchid sanctuary protects countless varieties of the flower, from the huge to the microscopic.

A magically clear, blue river that seems to spring from nowhere.

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

An Italian crevasse filled with abandoned buildings gives visitors a look at the world without humans.

It's always summer at the beach inside this former airship hangar.

The world's largest bioluminescent area was undiscovered by science until 2005.

Explore the complex ecology of this multifaceted nature preserve by riverboat.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Sanctuary on a ridge near an ancient shrine to a "Black Madonna" built by the founder of Opus Dei.

A breathtaking canyon offers stunning views and frightful pathways through an ecological paradise.

The mysterious, fantastical woodland inspiration for "The Lord of the Rings."

The convergence of two currents makes this a surprisingly pleasant getaway in the Arctic Circle.

This everlasting lightning storm may be the world's largest generator of ozone.

A sprawling Baroque park with 300-year-old hydro-pneumatic waterworks.

This Brazilian astronomy museum allows guests to gaze at the stars through their telescopes each weekend.

Countless grotesque faces stare out from this eerie Prague art wall.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

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

Crumbling remnant of Rio's colonial past tucked behind Corcovado mountain in the neighborhood of Cosme Velho.

Try not to get lost in this picturesque Brazilian labyrinth of the dead.

Once a strategically imperative naval base, portions of this Bermuda dock complex now serve cruise ships.

The lesser-known cousin of the Great Pacific trash island.

The birthplace of both the Atomic Age and Godzilla, and the namesake of the bathing suit.

An enormous concrete structure built over a nuclear crater.