At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

Architectureal fantasy quarter of Rome.

The yawning maw of this pagan visage is said to bite off the hands of liars.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

An alchemist's "magic door" stands in the middle of a Roman park.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

An abandoned train station in Munich constructed for the 1972 Olympic games.

One man's personal kunstkammer, museum and shop.

The patron saint of spinsters grasps a container of dried blood.

A museum dedicated to a Cold War era sausage.

One of the world's heaviest musical instruments towers within a popular urban park.

These former Nazi anti-aircraft towers offer a singular view of the north of Berlin in the summer, and a sanctuary for bats in winter.

An abandoned swimming pool decays on the outskirts of Berlin.

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

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

Super-heavy Nazi architectural experiment.

This Berlin island is home to a flock of free-roaming peacocks, as well as a historic ivory folly.

A state-of-the-art medical facility from the Imperial era is now a derelict ruin.

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

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.

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

These brass bunnies honor the rabbits that dominated the no-man's-land around the Berlin Wall.