Bask in the 19th century grandeur of an eccentric Freemason millionaire's private gardens.

Week-long block party becomes a competition for the best decorated street.

This former Baroque palace on the historic Calle Montcada is a rare architectural gem and was once the meeting place of an aristocratic scholarly society.

Construction of Barcelona's iconic (but controversial) church is expected to be completed in 2026—a century after the death of its architect.

Remarkably intact Roman stone fortifications have encircled this Spanish city for centuries.

A tiny church on a man-made island in the Adriatic.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

An ancient and majestic fortress that played an integral role in Portugal's road to independence.

This unreal Portuguese palace looks as though it's made from a pile of different castles.

This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

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

Gaudí's famously flamboyant architectural style is on full display in this sprawling park and garden.

Long tunnels run under the ancient chariot racing circuit to the tower.

Stunning Roman aqueduct used for 1900 years and still standing.

An ancient knight and a symbol of the city's freedom.

Gargoyle head that brings good luck.

A musical instrument played by the sea.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

Where the lovelorn find a home for their sentimental keepsakes.

This small Slovenian town has become a magnet for microbreweries.

An otherworldly alpine pasture with its own unique microculture that recalls Middle Earth.

A whimsical bridge adorned with decorative dragons.

This abandoned Slovenian military barracks has become a punky-political art squat.

The first mosque in the world to receive electricity.