Built to transport German U-boats through the never-completed Masurian Canal, the locks near this Polish village are now home to a rope course.

A rare, flower-shaped example of Brutalist architecture in Switzerland.

This enormous abstract sculpture is part jungle gym, part elaborate noise-making machine.

The remains of the last Bosnian fortress to fall to the Ottomans are still standing.

This abandoned airplane hanger is said to have once been a top secret launch facility.

This ironic war memorial thumbs its nose at a campaign of inedible humanitarian aid food products.

A number of craters left by fatal mortar strikes have been filled with red resin to remember those lost during the Siege of Sarajevo.

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

A former bank seized as a sniper vantage point during the Bosnian War is now a secret graffiti art gallery.

Oriental bazaar in the heart of Sarajevo.

This historic cemetery was inaccessible for several years due to dozens of land mines.

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

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

This museum preserves the hand-dug tunnel that kept Sarajevo afloat during the Serbian siege.

The haunting ruins of a military fortress turned astronomical observatory sit on a Sarajevo mountaintop.

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

These warring psychedelic crags commemorate an unsuccessful military operation.

There's a mini version of Iguazu Falls hidden in the Balkans, and it's got a rope swing.

Bridge that died in war and was resurected.

This exclusive resort has completely covered a tiny Balkan island in a 5-star warren of guest rooms.

Former military fort and site of untold horrors during WWII, this island may become the Adriatic's next luxury resort.

On top of a resort town as old as the Bronze Age sits an incredible war memorial statue overlooking the beaches below.

A tiny church on a man-made island in the Adriatic.

This hidden garden boasts amazing views of Lyon.