This massive library holds what was once the largest book collection in the world.

A small island less than half a mile from Venice is a forbidden island with a dark and twisted past.

One of the oldest medical collections in Europe focusing on rare surgical instruments.

Ruins of a German Castle on top of a towering stone pillar.

This lower Manhattan bar is set up in an old bank vault that rests beneath a skyscraper that hides even more historic splendor.

A 200-year-old bar in the historic French Quarter refuses to give up its place in history, nor its role in securing ours.

A hospital closed seemingly in the middle of operations, leaving behind fodder for horror films and ghost hunters.

The ancient dwellings of the Puebloans, located in the cliffs of majestic mesas.

The site of the climactic scene from the classic horror film is now a historic landmark.

This iconic Parisian bookstore doubles as the "Tumbleweed Hotel" for traveling writers.

The feral felines of Roosevelt Island have a small army of allies and an abandoned hospital all to themselves.

Northern Ireland's Brobdingnagian stepping stones.

An underground mansion with fruit-bearing trees and grapes growing beneath the surface of central California.

The oldest stone house in Paris was built by its most famous alchemist.

The final resting place of New Orleans' most famous voodoo priestess.

Two stunning 17th-century libraries and a cabinet of curiosities.

A fiery crater has been burning in the Karakum Desert since 1971.

Enormous lake at the bottom of a unique cave system.

Towering basalt columns, a creation of fire and ice.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

The atmospheric road was never meant to be so creepy.

A submerged archeological park still holds the wonders of a Roman Sodom.

This volcanic cave lake is essentially hard proof that Iceland is the most magical place on Earth.

Macabre astrological automaton clock dating to the late 1400s.