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

Longest fortress system anywhere in Europe.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

Gargoyle head that brings good luck.

Legend has it fairies gathered at the site of this medieval castle.

This truly palatial work of Communist-era architecture now sits crumbling on a Croatian beach.

Yugoslavia's biggest underground airport lies in ruins.

Where the lovelorn find a home for their sentimental keepsakes.

A musical instrument played by the sea.

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

Perched on a spindly rock spire in a Greek archipelago, this lighthouse would make a perfect wizard's tower.

A cemetery in Barcelona's Poblenou district is home to this touching funerary statue, which depicts death in the form of a winged skeleton.

Gaze upon chocolate sculptures depicting everything from chariot races to Gaudí's famous church at this shrine to sweets.

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

A beautiful but toxic fountain of mercury.

This semi-secret storybook hedge maze is also the oldest garden in the city.

Berliners converted a bombed-out, disused lot into a community-run urban farm with its own cafe and bar.

Named after a militant urban guerilla, this famous former squat is a graffiti-covered stronghold of leftist culture.

An abandoned NSA listening post on Berlin's "Devil's Mountain."

A tour of underground Berlin takes you through WWII air raid shelters and tunnels used to smuggle people out of East Germany.

This heart-shaped island looks substantially less lovely after a recent bulldozing project.

One of the few remaining casualties of the London Blitz, this destroyed church has become an enchanting public garden.

This enchanting hamlet carved into the rock looks like something straight out of Tolkien's Rivendell.