This medieval tower is all that remains of the castle where Joan of Arc was held before being burned at the stake.

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

The sunken structure looks like the victim of a catastrophic flood.

This submersible road connecting a French island to the mainland is lined with safety towers for when the tide strands travelers.

A French library that makes sure its love of books is writ large... giant in fact.

This ancient theater was once the home of fierce gladiatorial battles.

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

The Church of the Annunciation was carved into the face of a cliff, just like the rest of the town of Haute-Isle.

A medieval church with largest and oldest collection of Renaissance frescoes in France.

The 16th-century church was kept in its ruined state as a reminder of the casualties of World War I.

The post-apocalyptic remnants of a bucolic town ruined by a plane crash.

A French valley with forests so lush it was nicknamed "the Small Amazonia of the Pyrenees."

An unusual number plate signifies the building's saucy past.

The remains of 40,000 humans, meticulously stacked in a tiny churchyard shed.

This bridge was constructed from the rubble of the infamous Bastille.

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

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.

The artist and his brother are buried in a landscape straight out of a van Gogh painting.

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

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

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

One woman's decades-long obsession with the "La Fée Verte."

An off-the-beaten-path boutique stuffed with an eclectic collection of upcycled goods.

BDSM, 1930s Style.