Medieval torture techniques with a modern conscience.

Island wonderland for communist autocrats.

Longest fortress system anywhere in Europe.

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

An ethereal glowing blue ocean cave in Croatia.

A miniature train-ride through Slovenia's largest cave system.

A musical instrument played by the sea.

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

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