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

Fragments of human bones are embedded in the walls of this quaint alley.

To fit bodies into this Renaissance crypt, they were first left to decompose in the crypt's rotting room.

A strange anthropomorphic stele with a mysterious inscription that has never been deciphered.

The mysterious remains of a martyred teenage saint are venerated inside a small country chapel.

A signal indicates the entrance to this alley, rumored to be a meeting place for witches.

A pair of gigantic baby heads greet passengers at Atocha Station.

This Bronze Age man spent millennia buried in a mine, giving his bones an eerie hue.

A curious memento mori hangs in the magnificent Cathedral of Segovia.

A controversial art piece that harkens back to local folklore.

Mysterious face-like images that appeared within an Andalusian house are surrounded by legends of the paranormal.

Part of the medieval watchtower is displayed in an otherwise ordinary parking garage.

A display of torture devices used in the Spanish Inquisition and other scourges of medieval Europe.

This stunning iron gate designed by Modernist architect Antoni Gaudí is filled with mythic symbolism.

The lengthy skeleton of one of the tallest Spaniards of all time is on display in Madrid.

An eccentric collection of antique items shares space with a prop-quality witchcraft museum.

Mysterious Spanish catacombs of unknown origins.

The morbid items in this small and hidden museum are not for the weak stomached.

One of the world's oldest universities houses an incredible collection of anatomical models, mummified body parts, and human bones.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

This macabre masterpiece of a mural is one of Francisco Goya's "Black Paintings."

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

A landscape decorated with enormous skull sculptures.

A museum dedicated to the Spanish occult in a town that was terrorized by the Inquisition.