"The most colorful grottoes of the world.

Terrifying derelict military hospital once housed a recuperating Hitler.

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

Home to 10,000 medical specimens including the remains of Rudolf Virchow's extensive collection of pathological specimens.

This historic stone bridge has an entire neighborhood clinging to its sides.

A fascinating insight into daily life in the Eastern Bloc.

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

A striking 12th-century-style castle built on the edge of a cliff.

This Nazi-built amphitheater was constructed on a sacred mountain site used by various German cults.

Super-heavy Nazi architectural experiment.

When German-Iraqi relations broke down, this embassy was vacated post haste.

A 12th-century fortress containing some of Berlin's oldest buildings.

This ancient ruined monastery has been destroyed by fire so many times that it seems like God hates it.

This Dresden church was purposely rebuilt Protestant after being demolished in World War II.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

The last bastion of Roman presence north of the Alps looms over a German town.

An old slaughterhouse now holds the largest collection of pig artifacts.

The narrowest street in the world is in danger of closing up entirely.

Over 12,000 hygiene oriented objects and exhibits.

This German "living museum" is maybe a bit too immersive.

The atomic museum in the basement of this German castle displays long strands of replica uranium cubes.

The castle where Martin Luther secretly translated the New Testament from Greek to German while in hiding.

A whimsical and twisted animatronic monster tour beneath the streets of Berlin.