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

The fantastic architectural models of a French traveler.

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

An icy lake tucked among jaw-dropping alpine panoramas.

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

France's most famous cemetery, with some of its most curious tombs.

This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

A musical instrument played by the sea.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

This Austrian museum celebrates the work of famous forgers and their inimitable imitations.

Each year melting snow turns these Austrian hiking trails into scuba zones.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Where a rare geological phenomenon created a section of rock that resembles a checkerboard.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

Natural cathedral designed by Italian artist Giuliano Mauri.

This enchanting 600-year-old tree is so magical it inspired the beloved tale of Pinocchio.

A beautiful and abandoned New York subway station from 1904, complete with chandelier.