One of the last umbrella repair shops in Paris upholds the nostalgic art of umbrella making.

Noirish green neon marks the location of one of the oldest private detective agencies in France.

Where the high court feasted, frolicked, and high courtesans put their royal lovers' diamonds to the test.

This natural French spring has been turned into a magical grotto by Roman and medieval constructions.

Twelve grave-faced marble angels guard the emperor's tomb at Les Invalides.

Do these monsters look familiar? The gargoyles on this church are all from pop culture.

An icy lake tucked among jaw-dropping alpine panoramas.

Hidden away in a modern library are the remains of one of the 18th century's most celebrated wunderkammers.

A 14th century bridge built as a fortress, where the devil lurks on one of its towers.

This historic island prison holds one of the dungeons from the Count of Monte Cristo even though it is a work of fiction.

This surreal statue brings a famous French novel about a supernatural cad to arresting life.

Hundreds of hidden passageways weave through the old quarters of Lyon.

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

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

The first green space constructed on an elevated viaduct.

Exquisite wall sculptures carved in secret by an early quarryman in an obscure corner of the Paris Catacombs.

In the best of all possible worlds, everyone will get a chance to see this statue in which Voltaire's heart is interred.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

The ruins of a Duke's bucolic dream, where camels once roamed alongside "Dutch" windmills and faux-Italian vineyards.

A subterranean shelter remains intact under a busy Paris railway station.

Statue of death tucked in the University of Medicine courtyard.

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

This French ghost town from World War II has been left as a memorial to German atrocities during World War II.

Egyptian Revival movie palace abandoned for decades and restored in 2013.