The only gulag ever to exist in socialist Yugoslavia.

Humble beginnings for one of the world's most famous scientists.

This Croatian fairytale castle is slowly falling apart thanks to years of neglect.

A forgotten monument to Yugoslavian freedom.

An abandoned brutalist monument whose history has been lost to the ages.

A chain of 16 wondrous lakes formed as a result of the gradual dissolution of soluble layers of bedrock.

Yugoslavia's biggest underground airport lies in ruins.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

This brutalist monument is inscribed with 9921 names of Yugoslav partisans who perished during WWII.

This former estate of a fascist leader is now a burnt out ruin leading to a system of secret tunnels.

This scale model of our solar system hid in plain sight for years before a physics team sought out all the planets.

Where the lovelorn find a home for their sentimental keepsakes.

Croatia's towering concrete blossom grows from the site of a World War II concentration camp.

This stunning, out-of-the-way Croatian monument commemorates a community's uprising against occupying fascist forces.

This huge metal monument is slowly being stripped to its concrete skeleton.

Take respite inside this jaw-dropping church while climbing the volcano where Georgia's Prometheus was once chained.

This ancient village and its adjoining cemetery have a beautiful history of death and remembrance.

Ancient rock-hewn town that witnessed key events of Georgian history.

Small church on top of a huge rock column.

These Stalin-era industrial 'death traps' hang lifeless above the city

Fortified homes of highland warriors that are still in use today.

The second largest in the world, this massive underground void has its own subway.

A shipwreck named Desire at the shore of Batumi.

Ruins of a former government building destroyed during the Georgian-Abkhaz war in the wake of the fall of the Soviet Union.