A cave in southern Italy adorned with thousand-year-old Biblical frescoes existed in obscurity until fairly recently.

An abandoned quarry hides an open-air gallery of huge sculptures, some made from the rubble of 9/11.

A 1,000-year-old church holds the bones of the Christian martyrs who died hiding inside it.

Southern Italy's spinning top village.

Dramatic sea stacks adorn the coast of this small village on the Adriatic coast.

One man's quest to fix his toilet unearthed over 5,000 artifacts spanning more than 2,000 years of history.

The Slovenian architect designed many landmarks in the capital city, including his own dream house.

The "dragon babies" of southeastern Europe.

Castle and secret tunnel withstood a siege until its owner was killed by the Holy Roman Empire, while sitting on the toilet.

One of the largest caves in the world open to the public.

During World War II, this rice mill became a Nazi concentration camp.

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

The walls of this medieval church are covered with perfectly preserved frescos, including a pristine example of the Dance of Death.

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

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

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

Island wonderland for communist autocrats.

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

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

For over 40 years, this quaint little house has teetered on a rock in the middle of a river.

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

Gargoyle head that brings good luck.

Longest fortress system anywhere in Europe.

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