Just a few miles from Novalja, a strange geological oddity has left scientists baffled.

A forgotten monument to Yugoslavian freedom.

This abandoned Croatian stronghold never saw a great deal of conflict but it is still a beloved relic nonetheless.

Now abandoned, the world's first torpedo factory is crumbling into the sea.

A tower marking the spot where Yugoslavia began its resistance against the invading Nazis stands neglected, but not quite forgotten.

Formerly Yugoslavia's "forbidden island," this sleepy little city still holds the abandoned remains of military strongholds.

Croatia's "hairy stone" fortress is one of the most well preserved Istrian castles.

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

The now-overgrown beach resort was once frequented by Yugoslav military elite.

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

Legend has it fairies gathered at the site of this medieval castle.

This truly palatial work of Communist-era architecture now sits crumbling on a Croatian beach.

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

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

Where the lovelorn find a home for their sentimental keepsakes.

An ethereal glowing blue ocean cave in Croatia.

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

A field filled with carved medieval tombstones called stećak.

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

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

This surreal memorial/cemetery is a necropolis of crumbling stonework and puzzle-shaped headstones.

A forgotten and crumbling Yugoslav monument to the victims of fascism.

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

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