This mine is home to the largest man-made hole in Europe.

The first recognized Neanderthal remains were found in this now-lost cave in 1856.

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

A top-secret bunker now turned museum, is an eerie look at what life would have looked like in the event of nuclear war.

This German art chapel is perfect for those who like their worship hard, modern, and utterly alien.

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

Walk through living pictures and music in the Cathedral of Images.

Now a memorial, this factory was once used as a concentration camp for artists by the Vichy government.

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

This little train station is forever immortalized in film history.

For a brief time in 1960s France, families could climb into a tiny submarine and be pulled along an underwater journey.

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

This historic stone gate tower is now just a lonely relic in the middle of a swamp.

A small Byzantine church lost in the middle of the mountains of southern Italy.

This church carved into the rocks is full of enchanting stone statues.

A fortress off the West coast of Portugal that dates back to 1502.

An early work of the architect Álvaro Siza Vieira, these swimming pools blend into the beach.

A memorial to the nearly 10,000 American soldiers laid to rest on the beaches of Normandy during WWII.

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

A small but charming botanical garden that contains many exotic plant species.

Building owners can take out tiles for free at this repository for historic building materials.

A perfectly circular lake is formed by the crater of an ancient underwater volcano.

A 19th-century mansion houses the largest collection of gin in the European Union.

The largest ice cave in the world is thought to be the entrance to hell according to Austrian legend.