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

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

A Trabant car, a kangaroo statue, and a plethora of plants take over this abandoned-factory-turned-bar.

This former quarry is now a picturesque gorge that hides a sunken lake.

Eighty million natural history specimens call this gargantuan museum home.

A former Latvian headquarters of the brutal KGB secret police is now open as a grim reminder of their atrocities.

The oldest housing complex in Riga is a mini timeline of architectural trends.

3,000 market stands in five former Zeppelin hangars.

Over time, this castle grew to encompass the entire island.

This former KGB building is now a museum memorializing the people who suffered during the Soviet regime.

An abandoned masterpiece of Soviet Brutalist architecture.

A curious art park at the geographic center of Europe is home to 3,000 television sets and other wonders.

A wealthy aristocratic family built this Disney-worthy, fairy-tale castle.

This free museum is building a collection of books that are banned, censored or burnt around the world.

The secret cells in the basement of the KGB's Estonian "Grey House" have been preserved as a grim Cold War museum.

A former imperial sea-fortress and Soviet prison.

This Soviet-era "closed town" was a top secret uranium producer often left off of maps.

Rusted cars, trucks, and buses form a fascinating collection of Soviet-era machinery.

A bridge destroyed three times: once as a ruse, then in an actual attack, and finally for the movies.

This abandoned Olympic skiing facility still bears the scars of the Siege of Sarajevo.

This top-secret nuclear bunker hidden in a Bosnian mountain has been converted to a modern art exhibition space.

A war-torn Olympic relic is being overtaken by graffiti and nature.

This cluster of little wooden huts once ground local farmers’ wheat into flour during the days of the Austro-Hungarian Empire.

Bridge that died in war and was resurected.