Resting in the middle of an Austrian river, this sci-fi "island" lets people cross in neon style.

Fantastic stories on a miniature railroad.

Austria's ultra-modern art museum looks like Cthulhu's giant alien heart.

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

A musical instrument played by the sea.

Trimmed trees grow alongside the graves like topiary tombstones.

Island wonderland for communist autocrats.

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

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

This modern, multimedia museum takes visitors on an evolutionary journey back in time.

Colorful power station with a chimney equipped with a gallery for exhaust monitoring equipment.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

This massive subterranean fissure is known as the "underground Grand Canyon."

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

The "dragon babies" of southeastern Europe.

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

Inside this small chapel tucked away in the forest is one of the most well-preserved Danse Macabre frescos.

This former estate of a fascist leader is now a burnt out ruin leading to a system of secret tunnels.

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 135-year-old weather station studied the effects of the climate on human health.

Now abandoned, the world's first torpedo factory is crumbling into the sea.

Just a few miles from Novalja, a strange geological oddity has left scientists baffled.

Humble beginnings for one of the world's most famous scientists.