This peculiar border irregularity is the only way to legally enter Russia without a visa.

A collection of old neon signs from all over Poland line a secluded courtyard.

A floundering Polish shipyard was once the soul of the Solidarity movement that capsized communism.

A huge wooden clock that is so beautiful its creator was forcibly blinded.

This antique thermometer honors the creator of the first universal temperature scale.

The traditional Polish croissant, folded 81 times into the shape of a horseshoe, is a legally protected cultural treat.

This Nazi ruin was the site where Hitler was almost blown up by a suitcase bomb.

A national collection of Communist-era musical posters.

A 20th-century picture show in 3-D.

A tribute to the Polish insurgents who fought in the failed attempt to end their city's Nazi occupation.

A hidden art gallery in an abandoned Warsaw fort.

To the great disappointment of doomsdayers, this codex merely contains records of the Moon and Venus.

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

This unusually shaped mountaintop tower looks like a UFO floating over the city.

Bohemian paradise covered in majestic forests.

An Orwellian sculpture with eyeball cameras watches passersby.

A steampunk-styled three-floor factory churning out art, activism, and electronic beats.

What looks like a crashed Zeppelin is actually a bright, airy reading room perched atop a modern museum.

Two stunning 17th-century libraries and a cabinet of curiosities.

The history of occult science is turned into a creepshow at this lurid Prague tourist attraction.

Buried five stories underground, this Soviet bunker is packed with gas masks and Cold War paraphernalia.

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

Street artists transformed an abandoned air vent into the beloved Star Wars robot.

The last municipal pneumatic post system in the world was in operation for over 100 years, and may run again.