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

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

Double spiral staircases are not unheard of, but they are very rare.

Apartment complexes built into huge repurposed natural gas tanks.

A spherical "micro-nation" in the heart of Vienna.

Water mills built into a cave in the 17th century are powered by a subterranean river.

These spindly, stone-capped formations are the product of glacial deposits and thousands of years of erosion.

Visit Europe's largest subterranean waterfall, carved by water from the glaciers of the towering peaks surrounding the valley.

A treasure trove of scientific instruments from the 17th and 18th centuries.

This ossuary is more than five centuries old and is heralded as one of the finest in Switzerland.

Europe's largest dinosaur museum was founded by a passionate autodidact.

The bears of Bern have been a city highlight for over 500 years.

For centuries no one knew there were hundreds of bones and precious artwork hidden beneath this Swiss church.

This lush, scenic spot was carved by the turquoise waters of the Radovna.

Thousands of medieval skeletons lie just beneath Kranj’s main square.

A public work of art that also provides some relief from the summer heat.

The world's oldest grape-producing vine has survived four centuries of turmoil and even has its own anthem.

The "dragon babies" of southeastern Europe.

An otherworldly alpine pasture in Slovenia with historical ties to WWII and architecture that recalls Middle Earth.

The walls of this medieval church are covered with perfectly preserved frescos, including a pristine example of the Dance of Death.

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

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

A whimsical bridge adorned with decorative dragons.

This one-time health resort was used by aristocrats around the world.