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

Colorful concentric circles honor a small Croatian town's supposed spot at the nucleus of it all.

The oldest arboretum on the Dalmatian coast doubles as the gardens of Kings Landing in "Game of Thrones."

The Renaissance-era courthouse is a relic from the fortified town's centuries of Venetian rule.

Now harmless, this looming post struck fear into the heart of medieval troublemakers.

Built as an anti-fascist tribute, this surreal Yugoslav memorial became an unwelcome symbol after the Croatian war for independence.

Island wonderland for communist autocrats.

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

When a supermarket opened up shop within a medieval building it became protected by UNESCO on a technicality.

An eclectic art form practiced by untrained masters is celebrated at this museum in the heart of Zagreb's old Upper Town.

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

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

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

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

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

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

A wunderkammer of gold and silver reliquaries and ancient saintly bones.

Longest fortress system anywhere in Europe.

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

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

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

Gargoyle head that brings good luck.

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

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