The hidden lair of an alchemist rediscovered in a 2002 flood.

An old asylum graveyard that's been abandoned for half a century attracts those seeking a dark thrill.

A collection of anatomical samples from one of the first anthropologists to suggest that humans reached North America by crossing the Bering Strait.

A concrete plant shaped like four giant soldiers commemorates one of the most decisive battles of the Napoleonic Wars.

Before serving as James Bond's Casino Royale, this Victorian-era spa catered to the world's elite.

A larger-than-life statue of the German revolutionist stands proud in a small town where he never lived.

Be(w)ar(e) the moat around this historic Czech castle.

Microscopic scenes; some call it novelty, some call it art.

A turn of the century building boasting some of the most beautiful art nouveau architecture in Prague.

The first museum in the world devoted to sexual gadgetry.

A former top secret nuclear fallout shelter now operates like a hotel stuck in the Cold War.

A peculiar clock commemorates a historic victory won by ringing the noonday bell an hour early.

A cheeky architectural easter egg.

The housing complex served as an anti-fascist fortress during the Austrian Civil War.

Amsterdam's Red Light District leaves little to the imagination.

Rotterdammers' dirty minds gave this Santa a dirty nickname and cursed it to a life of wandering.

'The Letters of Utrecht' lays out a ribbon of poetry one letter at a time, with no final verse in sight.

The bridges portrayed on EU currency aren't fictional anymore.

This still-celebrated home was a radical architectural experiment in 3D De Stijl.

Visit the ancient, mysterious Roman catacombs ... in the Netherlands.

This centuries-old gothic monster has been converted into a sprawling, glossy bookstore.

A hidden church in a hidden courtyard tells the story of the Miracle of Amsterdam.

A preserved college lock-up that recalls a clubhouse approach to discipline.

A collection of artworks exclusively created by the mentally ill that was almost burned by Nazi culture police.