This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Located in the house where Gustave Flaubert was born, this odd museum has more to do with medical grotesquery than the Western novel.

Sacked by Vikings, blessed by William the Conqueror, dealt a fatal blow during the French Revolution—these ruins have seen it all.

Striking occult iconography on a medieval German church.

This ancient Irish religious site is covered in ancient carvings, many of which have barely aged.

One of the most popular megalithic sites in Ireland stands as a humbler version of Stonehenge.

An encyclopedic collection of mammal penises.

A church filled with the bones of hundreds of virgins martyrs—or so they say.

Artfully arranged bones of 5,800 Austrians.

Terrifically morbid cemetary and site of famous Paracelsus' grave.

The personal charnel house of Anton Bruckner.

An Austrian house of bones filled with hundreds of intricately painted skulls.

For centuries no one knew there were hundreds of bones and precious artwork hidden beneath this Swiss church.

The resting place of 18th century German mummies.

A monument to the "father of modern warfare" Gustav II Adolf.

A Parisian cemetery where the elite and artistic are interred beneath an eccentric collection of tombs.

A horde of stray cats rule in this secluded Parisian cemetery under a bridge.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

Commonly acknowledged as the only public monument to the Devil himself.

Thousands of well-dressed mummies below a monastery.

Every inch of this chapel is covered in craftsmanship from across the world.

Where Aleister Crowley taught magick in "La Chambre Des Cauchemars," his "Chamber of Nightmares."