The land is full of geologic eye candy, such as otherworldly spires, mushroom-shaped hoodoos, and prehistoric fossils.

Islanders once used this dramatic, otherworldly landscape to hide their cattle from Viking raiders.

Sacked by Vikings, blessed by William the Conqueror, dealt a fatal blow during the French Revolution—these ruins have seen it all.

A fortress on this island housed the mysterious prisoner known as the "Man in the Iron Mask" for more than a decade.

A museum dedicated to one of Paris’s most famous residents, tucked into a corner of one of the city’s most famous squares.

One of the most beautiful bookstores in the world hides a neo-Gothic interior behind an art nouveau facade.

The former site of an all-but-forgotten colonial landmark is now remembered by an often overlooked bas relief.

A men’s restroom became a sandwich shop.

A onetime gangsters' hideaway where you can dine on steaks, fine wines, and cigars just like they once did.

An isolated 17th-century chapel on a remarkable site once dedicated to Celtic sun worship.

Dr. Strangelove-esque tours reveal the inside a bunker once reserved for Stalin himself.

The legendary building that needed ghostly approval before being built.

A brilliant turquoise lake in the mountains.

Each spring this woodland floor is carpeted with purplish flowers as far as the eye can see.

Legend has it a commoner volunteered to be buried alive in the foundation so that the great fortress could be built.

Hidden in the shadow of a rocky fortress is one concubine’s long-forgotten legacy.

A prestigious learning institute of old Shanghai.

Rome's semi-secret peephole vista is also a former Crusader stronghold.

A meditative space out of a fantasy story.

A terrific purveyor of natural history objects and curios.

The only Bahá'í house of worship in North America and one of only a handful worldwide.

You can row a boat through this ancient underground reservoir.

The headquarters of a secretive order is also a beautifully-designed park.

A secluded, little-known temple hidden amid the dense jungle.