A kaleidoscopic warehouse-maze of handmade neon signs.

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

A 13th-century Swiss castle houses a collection of artifacts from the Polish diaspora.

A meteorite-bounded town in Bavaria.

The world's most delightful not-NOT-religion welcomes visitors to the town of Templin, just like its more stoic peers.

This museum tells the story of lake dwellers from 4000 BC to 850 BC, replete with stilt houses and goats.

Remnants of an exploded schooner and wrecked submarines form a breakwater.

Ruins of a German Castle on top of a towering stone pillar.

Started as a kitchen garden, now the second largest botanical garden in the world.

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

An eerie, derelict amusement park in Berlin.

This jaw-dropping 19th-century bridge uses its reflection to form what appears to be a perfect circle.

150 or so scrounged-up lamps, chandeliers, and lanterns light up this alley in central Athens.

The rocky remains of an ancient Greek forest.

Cave on extinct volcano, once home to famous mathematician Pythagoras.

A Bronze age settlement on the Greek island of Santorini might have been the inspiration for Plato's Atlantis.

A minotaur, a labyrinth, and a dubious restoration pull in visitors from around the world.

A spectacular cave and a beguiling lake.

Monasteries on rock pillars, once accessible only by frayed ropes.

This little museum is packed with information about the region's past and present biodiversity.

An interactive exhibition space dedicated to the kinetic sculptures of Swiss artist Jean Tinguely.

The oldest surviving wooden bridge over Rhine lets travelers cross easily from Switzerland to Liechtensten.

The idyllic island where the philosopher Jean-Jacques Rousseau spent “the happiest time of his life.”

Abbey built on the ruins of Roman catacombs.