Abandoned railway line circling the city of Paris.

A mud statue stands in the dark tunnels, seeming to hold up the weight of the city above.

1920's reinforced concrete church by architect Auguste Perret changes the face of modern design.

Shattered columns and Egyptian pyramids outside of Paris.

This stunningly massive housing complex is a go-to filming location for dystopian sci-fi cinema.

Ghosts of France's colonial past.

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

A daring D-Day assault by U.S. Army Rangers is commemorated atop the high cliffs of this strategic point.

One of the oldest and largest wooden churches in France was very evidently constructed by shipbuilders.

Two small chapels housed inside an ancient tree.

These ruins reveal the remarkably intact layout of a Roman marketplace.

An underground city of ancient quarry tunnels hid thousands of Allied soldiers in WWI.

Underneath a chalk hill in France lies what Hitler hoped would be the underground launching base for a devastating new weapon.

These rustic holiday homes are made from discarded fishing boat hulls.

Deep in the limestone cliffs of the Alabaster Coast, a German fortress built during World War II.

A centuries-old complex of hand-dug stone chambers has sheltered locals in times of trouble.

This "social palace" housing complex created a relatively stable and self-contained worker's society... for a time.

This small commune with an even smaller name appears to have an unlikely amount of dead ancestors.

This striking fort on the Maginot Line looks just as it did after being destroyed in the Fall of France.

A swath of France so devastated by war it is still forbidden to go there.

This modern French ossuary contains the jumbled bones of 130,000 WWI soldiers.

Site of one of World War I's most horrific scenes.

This building’s ghostly exterior reflects its former lives as a prison, school, and funeral home.

This 14th century wine cellar is home to the oldest barrel-stored wine in the world.