The restaurant keeps a hidden séance room on the second floor and reserves a table for the spirit of the former owner each night.

The former home of an Italian artist is now a shrine to his ambitious works.

The engineering wonder and pleasure dome of a much-maligned emperor still holds undiscovered secrets.

Architectural monsters are devouring this palace's every door and window.

The underground sanctuary of a mysterious ancient cult.

At the crypt of St. Mary of Eulogies and the Dead you are left alone to ponder mortality among piles of skulls.

Harlequin costumes, signed scripts, and armor-wearing puppets.

A collection of objects supposedly singed by the hands of souls in purgatory.

The yawning maw of this pagan visage is said to bite off the hands of liars.

The Pope’s secret escape route.

Ever hear of the Milazzo Cage?

This ritzy Italian market is built around a statue of an unforgiven heretic who was burned for his belief in an endless universe.

A master of trompe-l'oeil creates a stunning, tourist-fooling dome out of a flat ceiling.

This ancient Roman prison is decorated with an upside-down cross not as blasphemy but as saintly tribute.

Installed in an act of one-upsmanship, the annual sundial in this church is also a symbolic victory for the Gregorian calendar.

The crypts of Capuchin friars decorated with the bones of over 4,000 friars, including an entire "crypt of pelvises."

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

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

The first museum in the world devoted to sexual gadgetry.

Macabre astrological automaton clock dating to the late 1400s.

Despite attempts by local police to discourage it, Beatles-inspired graffiti has been a means for artists to air grievances for decades.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

Two stunning 17th-century libraries and a cabinet of curiosities.

Microscopic scenes; some call it novelty, some call it art.