These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.

Relics from as far back as the 16th century are on display in a city known for its playing card industry.

A Cold War command center is hidden under an idyllic countryside.

Burbling away in refrigerators are 105 sourdough starters from around the world.

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

The deserted pirate-themed restaurant still entices explorers.

This abandoned boat sits on a nude beach, is shaped like a UFO, and is covered in graffiti.

Crop circles inspired this whimsical garden in Germany.

Check out a shovel along with your Shakespeare.

A comprehensive collection of bonsai set in a beautiful campus.

This abandoned Brutalist treehouse is a hidden architectural relic.

Built entirely of interlocking pieces, construction of this Chinese Muslim house of worship required zero nails.

This small 16th-century church in Athens is almost entirely surrounded by a modern building.

This spectacular bridge supported by two gigantic hands looks like something out of a fantasy universe.

The best Tiki bar in Las Vegas.

Back in 1952, you could get a mushroom cloud chaser with your atomic cocktail.

This former lieutenant governor's home is brimming with curiosities.

James Turrell's total color immersion art installation, hidden on the top floor of a luxury handbag shop.

This incredible collection of vintage pinball machines can be played at 25 cents a pop.

The neon signs from Las Vegas' past find their final resting place at this unusual graveyard.

A giant open-air sculpture made of over 200 full-sized boats.

Nicknamed the "Museum of Horrors," this French anatomical collection has been fascinating visitors for over a century.

This stunning natural double arch, the largest in the Alps, went undiscovered until 2005.

These quaint French houses dangle precariously over a precipice.