For 20 years, this whale skeleton has been slowly dripping oil on the floor of the museum where it hangs.

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

On this wooded path, a stained-glass window creates a spellbinding forest cathedral.

Each year melting snow turns these Austrian hiking trails into scuba zones.

Underwater art project will double as a massive artificial coral reef to help regenerate the damaged ecosystem.

Hidden in a grotto 26 feet below Nottingham's oldest hotel, this stylish subterranean drinking den is notoriously hard to find.

The fanciest public restroom in New York City boasts fresh flowers, art, and a classical music soundtrack.

An underground city of salt.

The walls are decorated with whimsical murals painted by the creator of the Madeline franchise.

Ask nicely, and stewards of a centuries-old charitable tradition will give you free bread and beer.

This dizzying span over the ancient Algerian city was once the highest suspension bridge in the world.

This unusually shaped mountaintop tower looks like a UFO floating over the city.

Rare recess caves fill this unbelievably beautiful Ohio park.

An abandoned water sports stadium that has become a haven for graffiti and decay.

This old cement mine has been used as everything from a mushroom farm to a recording studio.

A once grand hotel is being retaken by the wilderness it once capitalized on.

These hellish-looking cliffs in the Canadian Arctic have been burning for centuries.

A B&B on a Victorian lighthouse station in San Francisco Bay.

An abandoned railroad tunnel is now filled with bioluminescent bugs.

Climb atop one of the world's longest and heaviest trains for an unbelievable journey across the Sahara Desert.

Dodge prohibitionists and slide through the telephone booth in Crif Dogs.

A magical sinkhole on the Yucatán Peninsula is adorned with mini waterfalls and hanging vines.

A library built during San Francisco's pioneer times is a student's retreat, bibliophile's sanctuary, and chess player's delight.

One man's eclectic collection of treasures found at sea.