If they push on just the right spot, even the weakest person can move this titanic boulder.

Statue of a decomposing prince that once held his heart in its hand.

This stunning French estate was so lavish that it landed its original owner in jail for the rest of his life.

A chapel on a volcanic core, marking the end of a successful journey.

The subterranean "lake" below the Paris opera house inspired the Phantom of the Opera's lair.

BDSM, 1930s Style.

This innocuous-seeming building is actually the remnant of a major wartime brothel.

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

The world's largest reflecting pool is just two centimeters deep.

A public park off the beaten path with a beautiful waterfall and 13th century Cistercian abbey.

The great Italian Renaissance painter was laid to rest here in the Chapel of Saint-Hubert.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

This off-limits room in the National Library of France is home to a system of pneumatic tubes, once used to bring books to readers.

This professional clown's home is an outsider art wonderland.

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

Museum in a swimming pool where the water still flows.

The recovered bones of martyrs slaughtered during The Terror are on display in this church crypt.

This life-size replica of the Statue of Liberty's flame is also a tribute to Princess Diana by default.

Two awe-inspiring globes from the reign of the Sun King hang from the ceiling of France's national library.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

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

The encased skull that is widely believed to belong to St. John the Baptist.

This little-known relic crypt holds stolen parts of a Roman Empress.

Hundreds of secret cabinets built into the walls of legendary poisoner's private work room.