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

St. Francesca Romana, patron saint of drivers, resides in the church she founded.

One of Catholicism's four major basilicas has a series of papal portraits that are said to predict the end of the world.

If you want to talk to the Pope you will have to stare down this surreal vision of Jesus rising from a nuclear hell.

Stone memorial that's said to predict the death of the pope and the site of the Cadaver Synod.

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

A Nesting Doll of Churches.

The skull of the patron saint of lovers lies in the Basilica di Santa Maria in Cosmedin—maybe.

One of several skulls claiming to belong to the beheaded St. John the Baptist is on display at this Roman church.

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

The famous winding walk at Chartres is surrounded in mystery and myth.

A museum of carnival attractions where you are invited to ride the rides.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

Remains of Roman amphitheater hidden in a sleepy quarter of Paris.

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

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

Saintly bones pressed into a wax effigy of a Catholic superstar.

A popular shrine where the Blessed Virgin allegedly appeared in 1830, displaying a holy armchair and two incorruptible remains of Lady Saints.

France's most famous cemetery, with some of its most curious tombs.

This former “ante-chamber to the guillotine” has been refurbished to illustrate the brutal history of French justice.

An "inside out" building in the historical center of Paris, featuring Europe’s largest modern art museum.

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

A mechanized clock where a man fights off a dragon, crab, and rooster.

Paris' linguistic guide to the international language of, yes, love.