You would never come across this tiny green oasis if you didn't know it existed.

The walls and ceiling of this Polish church are decorated with thousands of skulls, with another 21,000 skeletons just below.

The former Nazi concentration camp stands as a museum to remember this dark chapter in European history.

Enormous sandstone towers loom within a Czech forest.

Europe's largest natural bridge has a 19th century royal chateau built into its side.

This enchanting mountain plateau celebrates spooky local folklore.

A strange rock formation with numerous legends trying to explain it.

Nature is slowly overtaking this disused cemetery on the outskirts of Brussels.

The ruins of a castle sat decaying in this park for years before a massive renovation restored this area to its past beauty.

Marvel at this immense work of art that greets arrivals to the city.

Hollywood's most famous landmark, the "temporary" sign that has stood for decades longer than intended.

In all of the 29 years it was in operation, no prisoners ever escaped successfully... or so they claim.

Beneath the southern end of the Golden Gate Bridge is the “Gibraltar of the West Coast,” a fort built to protect the San Francisco Bay from naval attack.

These ruins disappear beneath the waves every winter.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

Resting on a hill overlooking the coast, these medieval ruins look completely deserted save for their restored chapel.

Napoleon's childhood home is now open for people to explore the beginnings of France's short general.

A whimsical brother of the nearby Fallen Angel statue takes the falling part quite literally.

In one of the smallest countries in the world stands an original Salvador Dalí sculpture.

This parody of ecclesiastical cloisters features famous figures from the 20th century.

The apartment where Pippi Longstocking came to life.

It is said that each of the white stones in the red facade of this medieval house represents the head of a murdered Swedish noble.

This snug medieval lane is one of the narrowest streets in the world.

A fire once nearly devoured this gorgeous 14th-century Gothic cathedral.