Invisible bridge parts the waters, invoking biblical images and preserving the ominous feel of an ancient moat.

Colorful and chaotic stacked hotel in North Holland.

Fighting the British and making game shows for over 150 years.

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

This stunning natural double arch, the largest in the Alps, went undiscovered until 2005.

The mental institution where Van Gogh created some of his most famous work now allows guests to walk in the artist's footsteps.

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

A Parisian exterminator's shop whose storefront displays stuffed rats hanging from traps.

An icy lake tucked among jaw-dropping alpine panoramas.

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

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."

An overlooked marble is the only surviving in-place 18th century example of the measurement that changed how we define distance.

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

Indents in the pavement are all that remain from a grisly death machine in Paris.

This museum houses an imposing skeleton army comprised of creatures great and small.

A favorite Paris bar for U.S. expats, including Gershwin, Hemingway, and James Bond.

Walk upon the mementos of the dead in this Parisian courtyard paved with medieval tombstones.

This charming cobbled backstreet is the most Instagramable street in Paris, much to the residents' annoyance.

The macabre collection of Jacques Sirgent, an expert scholar on the undead and all of their trappings.

Museum preserving torture methods from the past.

135 bronze medallions mark a French meridian line which once rivaled the hotshot Greenwich timeline.

Abandoned railway line circling the city of Paris.