A church of bones, decorated with 40,000 human skeletons.

The underground sanctuary of a mysterious ancient cult.

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.

Architectureal fantasy quarter of Rome.

The relics of dozens of martyrs are stored in a single chapel.

Perhaps the most beautiful of preserved saints, with a little help from Paris.

The site where Poe "in great distress, and ... in need of immediate assistance" likely died.

A grand Gothic Revival basilica with stained glass depictions of Montreal's religious history has only one soul resting in its crypt.

The house and graveyard used in the Stephen King spine-chiller.

Site of the creepy house used in Lucio Fulci's "The House by the Cemetery."

Final resting place of the actress famed for her roles in Dark Shadows and Dario Argento's Suspiria.

The sci-fi villain is a little-known inhabitant of the U.S. capital's largest cathedral.

Burial site more than 300 years old.

A toxic ghost town sitting atop a massive coal fire.

The final resting place of two (or three) presidents, one vampire, and 18,000 Confederate soldiers.

A peculiar mansion built by the troubled heir to the Winchester Rifle Company fortune.

A curious fountain that has no water and includes Satan, a crab, and 9 giraffes.

Town full of spiritualists, some of whom are mediums, is still in full swing after 130 years.

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

An Irish church where an 800-year-old mummy is reaching out of his coffin as if to shake hands.

The world's only international cryptozoology museum is host to an unrivaled collection of mysterious objects.

The mummified heart of a saint lives on in this church—after a brief hiatus when it was stolen.

A New England ghost town features a trail of boulders etched with intriguing life lessons.