A little church on a tiny island looks like something from a fairy tale.

This network of conjoined cellars was riddled with traps and supposedly allowed the townspeople to pretend their homes were deserted.

Europe's second largest ossuary wasn't discovered until 2001.

The world's greatest slide descends 18 stories from this looping mountaintop viewing platform.

Massive installation of Europe's negative stereotypes.

Underneath the city that invented pilsners are a series of historic tunnels that have been storing beer for centuries.

This former quarry is now a picturesque gorge that hides a sunken lake.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

The last municipal pneumatic post system in the world was in operation for over 100 years, and may run again.

In this cobwebbed old operating theater, you can practically hear the screams of the unanesthetized patients.

London's creepiest cemetery was once the site of dueling magicians and mobs of stake-carrying vampire hunters.

A Victorian natural history and ethnographic museum with wonderful turn-of-the-century, science-book-esque evolution displays.

A closed London rail station created to cart away the dead still bears the marks of attempts to make it less morbid.

Hidden beneath the streets of London is a secret subway that only carried mail.