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

The encased skull that is widely believed to belong to St. John the Baptist.

A swath of France so devastated by war it is still forbidden to go there.

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

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

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

The world's tallest bridge is also possibly the most elegant.

The sunken structure looks like the victim of a catastrophic flood.

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

Hundreds of secret cabinets built into the walls of legendary poisoner's private work room.

This medieval tower is all that remains of the castle where Joan of Arc was held before being burned at the stake.

Sleep in a climate-controlled plastic bubble for the night.

Since ancient times these picturesque springs have been providing bathers with healing waters.

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

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

Beautiful carved tunnels.

This ancient Roman bridge and aqueduct still stands as a wonder of classical construction.

The great Italian Renaissance painter was laid to rest here in the Chapel of Saint-Hubert.

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

These quaint French houses dangle precariously over a precipice.

Ivy-covered Medieval tunnels cut through this charming town in France's Loire Valley.

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

A well-preserved medieval village nested on a rocky outcrop and surrounded by a network of cliffs, natural bridges and canyons.

The spiral staircase hidden inside this giant Parisian column was likely built for Catherine de Medici's astrologer.