Live a night as a Byzantine King, with a minibar and private jacuzzi.

Hidden just under the waters around this Turkish island are the ruins of a once great city.

A Turkish ghost town abandoned in a population exchange with Greece.

A Lycian city of the dead carved into the hillside of Southern Turkey, complete with startlingly human touches.

An abused and forgotten metropolis, abandoned for centuries.

This famous city eluded concrete detection until the early 2000's.

A deadly ancient portal to the underworld.

These tombs were built into the side of a mountain so that ancient angels could reach the dead.

A marvel of Byzantine engineering under the streets of Istanbul.

In this historic region, homes and churches are carved into ancient volcanic rock formations.

Roman ruins top white travertine terraces formed by ancient hot springs.

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

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

Large, airy hallways hide within an impenetrable fortress that beckons urban explorers.

Once a state-of-the-art tuberculosis treatment spa, these ruins are now ruled by paintball players.

This huge metal monument is slowly being stripped to its concrete skeleton.

The remains of a sunken military ship wreck visible through clear water.

An ethereal glowing blue ocean cave in Croatia.

A naturally beautiful, seemingly bottomless deep blue spring.

A grotto-like lodge decorated with gilded mosaics, rocks and a noisy waterfall was the setting for the most sumptuous pleasure house of 1900s Europe.

An outsider folly near Madrid.

Abandoned for decades, trains still pass through the now-restored remains of one of Madrid's first metro stations.

This funky former tobacco factory is one of the most striking examples of Madrid's cultural diversity.

The oldest restaurant in the world is this old-world Spanish eatery, still known for its suckling pig.