Fur-lined metal pod dangling in the French countryside.

An architectural oddity of six stories, accessed by graceful ramps.

This church looks more like a spaceship than a house of worship.

One of the greatest maze designer’s greatest mazes.

This whimsical castle of grottoes was the labor of love of a French postman, and one of the greatest achievements of outsider architecture.

At this monastery, monks make raw-milk cheese and use excess whey to create methane that powers their hot-water system.

From Carthage's Hannibal to riders of the Tour de France, many have crossed this scenic route through the Alps.

The ruins of a military fortification sit atop this mountain.

These quaint French houses dangle precariously over a precipice.

A chapel on a volcanic core, marking the end of a successful journey.

The largest underground church in Europe.

This impressive chasm is one of the longest natural underground cavities in the world.

The world's largest reflecting pool is just two centimeters deep.

A very uncommon water tank standing in the middle of the grapevines in Bordeaux nearly a century after its construction.

A young Gustave Eiffel assisted in the construction of this skinny metal observation tower.

Bordered by forest on three sides and the ocean on the other, the Great Dune of Pilat is the highest sand dune in Europe.

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

The evocative ruins of a medieval village.

Thanks to a clever legal loophole, this mountainside wine shop sells a hybrid cuvée that's been outlawed for nearly a century.

A natural arch carved by a river gave its name to the so-called "Cave of Forgotten Dreams."

This otherworldly French waterfall looks like its waters have turned to stone.

The construction of a tram line unveiled hidden remnants of the old medieval city.

A medieval military street hidden beneath a charming French fishing village.

This mountain trail inspired Nietzsche to complete his magnum opus.