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

This massive subterranean fissure is known as the "underground Grand Canyon."

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

This incredible stone temple is a monument to death, victory, and fantasy architecture.

The many—66 to be exact—faces of the German forest.

These historic defenses ensured the city within would survive hundreds of years of occupations, sieges, and invasions.

A curious cave church carved into the face of a cliff.

A tiny church on a man-made island in the Adriatic.

Its frescoes depict the likeness of Marshal Tito, Karl Marx, and Friedrich Engels burning in hell.

A futuristic, brutalist masterpiece that is also strangely prison-like.

Christianity and Islam have clashed, yet here a Serbian Orthodox church and a mosque stand together.

A magical museum of fairy tale treasures near Cyprus' buffer zone.

The water here is so clear you can see the mysteriously sunken ship from the surface.

The ancient mosaics here are considered among the finest in the world, and serve as a stunning record of Greco-Roman daily life.

Breathtaking Byzantine paintings cover the inside of this 12th-century church.

For nearly 2,000 years this church has been waging war on local snakes by importing cats.

This 700-year-old Cyprus castle is the birthplace of the world's oldest wine, said to be toasted by Richard the Lionheart at his wedding.

An ancient necropolis of magnificent tombs.

Once part of an ancient international harbor, it's now an all-you-can-eat shrimp buffet for flamingos and other water birds.

A 1970s resort city now stands abandoned, caught in the middle of a divided island.

A crumbling ghost town with prime views of the dam that doomed it.

The ruins of a fairytale castle with a tumultuous history stand high atop the mountains.

The animals wander freely amid this gorgeous stretch of nature.

The eccentric midcentury home of a suspected mafia gun-runner.