100-windowed castle turned art gallery, built by one dedicated mason.

Limestone grottoes turns everyday objects into stone.

Figures of unknown origin carved into the surfaces of underground caves.

Down a cobblestone alleyway is a museum dedicated to Romanticism, with a secret garden.

A cave dwelling that was started by the Celts, expanded by monks, and finished by knights.

Ancient paintings known as the "Sistine Chapel of Cave Art."

One of the greatest maze designer’s greatest mazes.

This otherworldly French waterfall looks like its waters have turned to stone.

One of the largest ochre quarries in the world, hidden in a limestone landscape.

France's Lilliputian park displays over 100 of the country's monuments for visitor perusal.

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

A quaint medieval millhouse hovers surprisingly above the waters of the Seine.

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

Even France's favorite aquatic son Jacques Cousteau, couldn't get to the bottom of it.

Beggars were miraculously "cured" of their fake ailments when they returned home to this 17th century Paris slum each night.

Green labyrinth formed by a karstic maze hidden in a preserved oak forest.

This salt marsh in Southern France is as pink as the flamingos that inhabit it.

A colossal sculptural lion built by the same man who designed the Statue of Liberty.

Since ancient times these picturesque springs have been providing bathers with healing waters.

An architectural oddity of six stories, accessed by graceful ramps.

Jean Tinguely's bizarre monster sculpture is hidden deep in a forest.

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

A unique underground structure dating back to the 1st century BC.

These crumbling Nazi artillery bunkers are now fair game for massive graffiti projects.