Caves famous for the dragon-slaying saint who lived there.

This amazing pedestrian suspension bridge in the Swiss Alps would give Indiana Jones nightmares.

This lovely little bridge hidden in a Switzerland gorge is essentially a fairytale.

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

A beautiful lighthouse with as many steps as days in the year, as many windows as weeks, and as many levels as months.

This 1,400-year-old abbey was once a powerhouse for music and intellectualism known across Normandy.

Resting on a hill overlooking the coast, these medieval ruins look completely deserted save for their restored chapel.

This ancient theater was once the home of fierce gladiatorial battles.

Legend has it this 11th-century castle was paid a visit from the devil.

These medieval ruins have survived since the 12th century, even providing shelter from the Nazis.

The Argonaute submarine was the French navy's pride and joy in the 1950's.

The deserted pirate-themed restaurant still entices explorers.

This futuristic observatory at the top of the Pyrénées offers unrivaled views.

The 16th-century church was kept in its ruined state as a reminder of the casualties of World War I.

A medieval church with largest and oldest collection of Renaissance frescoes in France.

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

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

Lyon, France is home to two remarkably preserved Roman theaters, one dating back to 15 BCE.

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

A mosaic-tiled house built by graveyard sweeper Raymond Isidore.

This stunning French estate was so lavish that it landed its original owner in jail for the rest of his life.

This French castle is said to have once held the Holy Grail but is now a gorgeous mountaintop ruin.

A public park off the beaten path with a beautiful waterfall and 13th century Cistercian abbey.

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