This beautiful Croatian fortress is haunted by legends of forbidden love.

This military tunnel dates back to World War II and provides visitors with a little wartime adrenaline.

An ancient knight and a symbol of the city's freedom.

A full figure 4th century incorruptible saint lies in a glass coffin in Croatia.

When Croatia became independent of Yugoslavia, the splintering governments left behind these concrete tunnels.

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

One of the best-preserved Roman amphitheaters is still used today, but for less brutal events.

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

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

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

Longest fortress system anywhere in Europe.

This picturesque medieval monastery guards a small trove of historic treasures.

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

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

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

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

Yugoslavia's biggest underground airport lies in ruins.

Where the lovelorn find a home for their sentimental keepsakes.

An ethereal glowing blue ocean cave in Croatia.

An apparition of Virgin Mary in Herzegovina.

A field filled with carved medieval tombstones called stećak.

This picturesque monastery at the base of a cliff is a peaceful oasis open to all visitors.

The sad remains of a monument to martial arts legend and movie star Bruce Lee—in the middle of Balkans.

This historic timepiece is thought to be the only public clock in the world that keeps lunar time.