This massive chalk hill carving is one of England's most beloved giant horse geoglyphs.

High Victorian fantasy created a fairytale castle out of a ruined fortress in Wales.

This Roman amphitheater is said to be King Arthur's legendary Round Table.

Wander around the extensive remains of this 12th-century medieval church.

This unassuming stone is possibly the oldest Scottish memorial to the 13th-century knight.

This bronze cat looks out over the Linlithgow Canal.

The installation’s official name, “You Who Are Getting Obliterated in the Dancing Swarm of Fireflies,” says it all.

This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

This hill nestled in the Scottish lowlands was a ritual site for over 4,000 years.

The sacristy of this church contains remains and relics of members of the Aragonese royal family.

The remains of the left arm of the levitating philosopher-saint are kept in a 13th-century Neapolitan basilica.

Ancient pueblos built into the base of a natural canyon wall.

An homage to everyone's favorite prehistoric cartoon family.

A small canyon with petroglyphs and a seasonal waterfall, only a short hike from the remnants of old Route 66.

Stone pillars and a petrified wedding party in the hills of North Macedonia.

This 3,800-year-old site contains markers used to study the movement of the sun and moon and create a lunar calendar.

The largest Roman amphitheater in the Balkans once held over 20,000 people, but managed to lay hidden for hundreds of years.

Hundreds of thousands of concrete bunkers crowd Albania long after the fall of Communism.

A medieval bridge stretches over a sulfur-rich river that leads to year-round natural hot springs.

A naturally beautiful, seemingly bottomless deep blue spring.

A charming beach town in Turkey captures all the colors of the rainbow.

On the outskirts of the small village, an abandoned grassy field glitters thanks to the white stones of an ancient structure.

At this 16th-century monastery in rural Bulgaria, visitors can also spend the night.

These cascading falls resonate throughout the Bulgarian forest.