This abandoned coliseum was intended to be a grand Nazi rallying ground before it was halted at the end of the war.

Terrifying derelict military hospital once housed a recuperating Hitler.

An eerie, derelict amusement park in Berlin.

This former steel and coal plant is now a neon-lit industrial fantasia.

The music is over at the Ballhaus Riviera Ballroom, but the ballroom remains in haunting disrepair.

Once the tallest building in the world, this abandoned church is now a monument to the destruction of WWII.

The abandoned remains of this Victorian brewery hide crumbling bowling alleys and rusting industrial gear.

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

The ruined remains of the airport Claus von Stauffenberg departed in his failed attempt to kill Adolf Hitler.

The ruins of an abandoned crematorium haunt an eerie deserted German cemetery.

An abandoned swimming pool decays on the outskirts of Berlin.

Obscured within a ring of trees, this abandoned World War II relic hides on a German hillside.

A statue of Vladimir Illyich Lenin guards this abandoned building in the "Forbidden City."

These abandoned Cold War-era bunkers are now a designated refuge for endangered bat species.

A crumbling bakery where forced laborers from the nearby concentration camp toiled to feed their fellow prisoners and Nazi soldiers.