The hidden lair of an alchemist rediscovered in a 2002 flood.

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

A Victorian Gothic masterpiece housing a world-class collection of rare books and manuscripts.

This former abandoned hospital, a complex of stunning 19th century buildings, once housed 2,000 psychiatric patients.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

When you can afford only half a road, you build only half a road.

This churchyard arbor is surrounded by hundreds of gravestones placed there by author Thomas Hardy.

This South London cemetery holds the remains of more than 15,000 people.

The beautiful baroque library of the Hapsburg empire.

This weird abode has inspired everything from the "House On Haunted Hil" to a robot hunter's pad.

A surreal museum of extraordinary industrial objects.

A student driver's nightmare.

This symbolic piece of New Orleans architecture is also home to a few ghastly stories.

This medieval castle overlooking the Elzbach river looks just like it did hundreds of years ago.

A vast overgrown cemetery, once known as one of London's "Magnificent Seven."

A museum dedicated to the history of a terrifying secret police is now held in their former headquarters.

A narrow passage next to a cafe leads to a courtyard exploding with murals, tags, and paste-ups.

The signs of a long buried road can still be found hidden beneath a London sewer grate.

Deceased nuns were placed on stone chairs to decompose, while the surviving nuns prayed near the lifeless bodies.

Modern art meets modern convenience in possibly the world's most architecturally important public bathroom.

Monty Python fans will recognize this abandoned mine as the Cave of the Killer Rabbit of Caerbannog.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

The interior of this Serbian royal family's mausoleum is covered with exquisite mosaics.