The site of a concentration camp where inmates were made to take part in one of the largest counterfeiting operations in history is now hauntingly empty.

Germany's Glienicke Bridge has a shady history of clandestine meetings, espionage, and spycraft.

This conical hill was built as a testing ground for an engineer known as the Glider King.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

Started as a kitchen garden, now the second largest botanical garden in the world.

An eerie, derelict amusement park in Berlin.

Super-heavy Nazi architectural experiment.

Berlin's old airport.

Someone loved this song enough to carve all of its lyrics onto a tree trunk in a Berlin park.

Art and a pun, all in one.

This obscene artwork on the side of a newspaper office pokes fun at a rival paper's former editor-in-chief.

A museum dedicated to a Cold War era sausage.

A fascinating insight into daily life in the Eastern Bloc.

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

This unusual small wind turbine in Germany has only a single rotor blade.

No need to strap in for a "ride" on this walkable roller coaster.

This "floating railway" is one of the world's oldest monorail systems.

This painted Lego bridge is the product of over a century of locomotive history.

An abandoned underground bathroom is now a space for public art.

This strange building looks like a medieval fortress crashed into a 1960s Brutalist office block.

This small condiment museum makes all manner of mustards with a 200-year-old mill.

This giant glowing "beanpole" adds much-needed pops of color to an otherwise drab power plant.

One of the most iconic neon ads of former East Germany.

The glowing blue Nymphaeum of Emperor Tiberius.