One of downtown Berlin's last reminders of its Communist past.

Berlin's old airport.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.

An eerie, derelict amusement park in Berlin.

This series of Baroque passageways in Vienna's cultural center mix old architecture with modern art.

Apartment complexes built into huge repurposed natural gas tanks.

Op-art architecture designed for happiness.

A tropical paradise just a short trip from the opera house is filled with beautiful winged creatures.

Sitting in the basement of a castle, the largest wine barrel in the world is bigger than most apartments.

It's good luck to be mocked by this monkey.

This hanging crocodile is thought to be the "dragon" that once plagued a Czech city.

Europe's second largest ossuary wasn't discovered until 2001.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

A museum dedicated to a secret military hospital hidden beneath a castle in Budapest.

Budapest's Communist-era statues, banished to the suburbs.

A 19th-century artistocrat's mansion, turned into a library, hidden in a modern library.