This medieval village clings to a cliff in southwestern France.

The world's most famous cheese caves.

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

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

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

Every half hour, the flow of this unusual spring cycles between a rush of water and barely a trickle.

Historic medieval fortified city in southwest France.

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

The tradition of open-air secondhand and antiquarian bookselling in Paris dates back to the Renaissance.

Tiny memorials honor individual victims of the Holocaust.

On the Spree bank, discover one of the last reminders of a symbolic wall that divided, and was torn down by the people.

A fascinating insight into daily life in the Eastern Bloc.

Thousands of coffin-like pillars make up this controversial Holocaust memorial.

The most visited, and possibly most controversial, museum in Germany.

This small oxbow lake has rare giant river otters and some Seussian-sounding birds.

The world's largest clay lick, where parrots gather to snack.

Built on the remains of one the Incas’ most important gathering spots, this square keeps the spirit of a fallen empire alive.

Situated on a sacred Inca site, this 16th-century cathedral took nearly 100 years to build.

The large collection of pre-Columbian pottery might make you blush.

This geometric feat is a testament to the Incas' mesmerizing architectural abilities.

This Peruvian canyon is filled with geometric salt pools that have been being harvested since the Incan empire.

The stones of this Incan wall complex fit together so well you couldn't fit a piece of paper between some of them.

Huge stone depressions which may have acted as an Incan agricultural experiment.

If you’ve ever seen a picture of Machu Picchu, then you’ve seen a picture of Huayna Picchu—you just didn’t realize it.