The largest free-standing aquarium in the world resides in a hotel lobby in Berlin.

An eerie, derelict amusement park in Berlin.

Largest cave system in Africa.

An odd little fishing town that is inundated by tourists looking to be locked up in a cage and surrounded by great white sharks, because why not?

This African beach is home to thousands of rare mainland penguins that are known for their annoying voice.

A church of bones, decorated with 40,000 human skeletons.

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

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

A surreal statue honoring Prague's favorite literary son.

What looks like a suicide in progress is actually a statue of Sigmund Freud.

The first museum in the world devoted to sexual gadgetry.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

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

France's most famous cemetery, with some of its most curious tombs.

An underground city of salt.

This expansive bridge in the Canadian wilderness was originally just built for friends.

A working steam clock, one of only a few in the world, located in Vancouver's Victorian Gastown.

This abandoned Slovenian military barracks has become a punky-political art squat.

A whimsical bridge adorned with decorative dragons.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

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

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

This solitary monastery may hold the remains of Vlad the Impaler (but probably not).

Romania's triumphal arch looks out over Bucharest.