This narrow fjord-like bay is the largest ria in the Mediterranean Sea.

The oldest arboretum on the Dalmatian coast doubles as the gardens of Kings Landing in "Game of Thrones."

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

One of the best-preserved Roman amphitheaters is still used today, but for less brutal events.

Longest fortress system anywhere in Europe.

The now-overgrown beach resort was once frequented by Yugoslav military elite.

A miniature train-ride through Slovenia's largest cave system.

The Renaissance-era courthouse is a relic from the fortified town's centuries of Venetian rule.

Croatia's "hairy stone" fortress is one of the most well preserved Istrian castles.

Elaborately carved to showcase the glorious wealth that the age of exploration brought to the Portuguese empire.

This Industrial Age architectural and engineering gem helps visitors and residents alike traverse Lisbon, “The City of Seven Hills.”

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

A king's pet, a pope's gift, an artist's inspiration, and a tragic shipwreck.

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.

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

A Spanish town built into the cliffs.

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

Over two centuries old and counting, Madrid's massive botanical garden contains one of Europe's only desert environments.

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

Madrid's romantically ornate crystal palace has been offering shelter to plants and art for over a century.

Hundreds of stone stairs and a winding medieval bridge connect this haunting Spanish island to the mainland.

An ancient Egyptian temple in the middle of Madrid, Spain.

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