A gravity-defying "devil's bridge" that has a surprising architectural feature for its stability.

The grotto where Saint Ignatius of Loyola lived as a hermit for nearly a year.

The Gaudí-inspired building that was the start of Terrassenc modernism.

These ancient burial caves carved into the cliffs offer a glimpse into prehistoric funeral practices and Menorca's early inhabitants.

A ghostly mansion in the middle of downtown Tunis.

Some believe this abandoned Brutalist masterpiece inspired George Lucas's Sandcrawler.

The ancient heart of Tunis is an enormous maze of narrow streets and alleyways.

Village situated on a narrow volcanic escarpment.

Religious dwelling in a Spanish volcano.

A darkly erotic open-air statuary in Catalonia.

A historic structure inspired by Roman, Muslim, and Jewish bath houses.

These fly sculptures are scattered around the city and represent the patron saint of Girona.

Kissing the ass of this stone lioness has become a rite of passage in the city of Girona.

Designed by Gustave Eiffel before his famed tower.

Built on the foundations of an ancient Roman villa, the unique architecture of this castle on the Catalan coast was used as a set for 'Game of Thrones.'

A museum of alchemy and a basement laboratory all housed in an ancient building in a Gothic tower.

An enormous and lavish Gothic church in Czechia.

A church of bones, decorated with 40,000 human skeletons.

A bust of Franz Kafka spins in pieces, reflecting the writer's inner torment.

This spooky statue sits outside a famous Prague theater.

Around 100,000 bodies are buried below the medieval headstones, many of which mark graves with multiple bodies stacked up to 12 deep.

Synagogue built from the stones of Solomon's temple contains the golem of Prague.

A surreal statue honoring Prague's favorite literary son.

The slender brass strip in Prague's Old Town Square was used to tell time from 1652 to 1918.