This astonishingly geometric cave has inspired everyone from Jules Verne to Pink Floyd.

Housing the famous Norwegian ice-defying 19th century polar exploration ship.

One man's exploration of the human form, including the bizarre and delightful "Man Attacked by Babies."

An ancient Egyptian temple sits within a modern European museum.

Science meets wall art to highlight the beauty of famous mathematical equations.

A Dutch clog company in the town of Zaandam loves the wooden shoes so much it made a museum for them.

Rich with fauna and flora, nature-lovers can walk across the sea at this UNESCO World Heritage spot.

A 'living museum' in Leiden, the oldest of its kind in the Netherlands.

Birthplace of the "Cat in the Cradle" and a cluster of iconic, original windmills that let the Dutch tame the seas.

Oldest Museum of the Netherlands is a true cabinet of curiosities.

The world's largest historic armory was established by independent citizens to defend themselves from the wars of larger forces.

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

The world's oldest known salt mine.

The Habsburgs' royal collections of art and wonders.

An Austrian house of bones filled with hundreds of intricately painted skulls.

A historic observatory precariously perched at the "Top of Europe."

The alpine falls where Sherlock Holmes apparently met his demise can actually be visited.

This memorial commemorating fallen Swiss Guards of the French Revolution has been called the saddest stone in the world.

This Berlin island is home to a flock of free-roaming peacocks, as well as a historic ivory folly.

The fairy tale castle of the "fairy-tale king."

The big toe of this towering monument to a Croatian national hero is worn from years of superstitious rubbing.

The world's first zoo for microbes collecting the horrible and wonderful things living on and around us.

Model Trains and Much More in Hamburg.

A magnificent collection of imperial armor and weaponry.