A surrealist timepiece by the artist of melting clocks.

A counter-culture bookstore like no other hides in plain sight in the streets of Paris.

France's national museum of scientific and industrial instruments.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Walk upon the mementos of the dead in this Parisian courtyard paved with medieval tombstones.

Dedicated to the art of hunting, with juxtapositions of contemporary art.

Notorious artist squat renovated into legal studios.

This chest hospital with a dark, haunted past serves as a fitting set for horror films and a paradise for ghost hunters.

Cursed swimming pool left abandoned is now a favorite of filmmakers and ghost hunters.

This cemetery features modernist statues as strange as its name.

One of Antoni Gaudí's most classic buildings is well-known for its "dragon-back" design.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

One of Europe's largest supercomputers is housed inside of a disused chapel.

Hidden beneath the famous St. Peter's Basilica is a veritable city of the dead that may hold the remains of St. Peter himself.

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

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

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

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

An alchemist's "magic door" stands in the middle of a Roman park.

2300-year-old Roman road connecting the empire.

Gods clash with machines in a power plant regenerated as a museum.

This hill made entirely of ancient Roman jars was simply a garbage dump to the people of the time.

A mysterious chasm in the heart of the ancient Roman Forum, the Lacus Curtius was once believed to be a gateway to hell.

A Nesting Doll of Churches.