A subterranean world of tunnels links several buildings of this rare 19th-century asylum.

This picturesque ghost town is located on the banks of the Suwannee River.

This hauntingly beautiful cemetery outside a medieval citadel is full of winding paths and ivy-covered graves.

A spooky spot along the road where things mysteriously seem to move uphill by themselves.

A Romanian church built from one single oak.

Known as the Hintz House, this medieval pharmacy has been an apothecary's haven for nearly 450 years.

A stunning 18th century pharmacy and medieval chemist's collection.

This once-derelict building is now one of the most beautiful bookstores in the world.

Something's watching you.

Even drowned in an ocean of toxic waste, the remnants of this Romanian village stand tall.

The bust of Romania’s most notorious ruler, Vlad Dracula aka "Vlad the Impaler," keeps watch over the ruins of his medieval court.

Conspiracy theories and occult legends surround this mysterious natural rock formation.

The possible imprisonment of Vlad the Impaler here earned the medieval castle its nickname, "Dracula's Castle."

This elaborately decorated, fairytale-like Romanian royal palace is one of the most striking castles in Europe.

The legendary cliffside castle of three-time Voivode of Wallachia, Vlad the Impaler.

A small town Romanian cemetery filled with darkly humorous gravestones.

This fairy-tale castle would make Dracula (who is said to have been imprisoned there) jealous.

This massive underground salt mine now holds a sci-fi theme park in its depths.

Moss and stone turn this waterfall into an otherworldly liquid veil.

Light still pours into the ruins of this ancient Islamic observatory.

The Avenue of Mausolea is a series of grand palatial tombs.

The ceiling of Prohodna Cave in northern Bulgaria affords a peek at the sky via two deity-sized-eye-shaped holes.

Some North Carolina Cherokee have been keeping their history alive for decades with a single play.

Mile-long cave system near Great Smoky Mountains.