This picturesque medieval monastery guards a small trove of historic treasures.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

One of the longest natural sand beaches in the world.

Geological storytelling.

This species of wild goat stars in witchy legends and frolics among the park's eerie rock formations.

The oldest Roman lighthouse still in use.

Cliffside houses provide a spectacular view from their perch above the valley.

One of the few remaining ancient aqueducts described by Frontinus as 'the most solemn testimony of the Empire.'

This Navarrese cave's history of witchcraft and pagan ritual is not just embraced, but recreated each year.

These magnificent city walls rise from the barren sun-baked Spanish plains like something straight out of a fairytale.

These secluded and abandoned anti-aircraft defenses have become one the most scenic viewpoints in Barcelona.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

High in the clouds of San Marino sits an ancient tower with some curious prisoner graffiti.

This unique building in the main square stands out among the city's typically Baroque architecture.

These lesser-known Maltese catacombs date back over 1,700 years.

The eclectic seaside sanctuary caters to a rather fowl crowd.

A hidden tunnel of bones in one of Malta's oldest churches.

An abandoned set from the 1980 film "Popeye," claimed and repurposed as a theme park by creative locals.

A mysterious ancient elephant said to possess magic powers is now the symbol of a Sicilian city.

Stare out over the lagoon and beyond from this 10th-century campanile on the island where the city of Venice began.

Two stone columns flank the grand Venice square, but there were supposed to be three.

Over 100 towers were built in Bologna during the Middle Ages, but only 22 survive.

A line of abandoned, alien-like fortresses dot the mountains of North Italy.

The world's most active stratovolcano is almost always erupting.