This 1,300 year old monastery built atop a single rock was once only accessible depending on the whims of the tide.

Ivy-covered Medieval tunnels cut through this charming town in France's Loire Valley.

Guests can stay at a hotel in the former French abbey where lie the tombs of King Henry II and King Richard the Lionheart.

Hundreds of prehistoric stones, arranged in perfect lines in a French field.

This Catskills museum preserves stumps from the earliest known fossil forest on Earth.

The floor of this spectacular Baroque sanctuary is covered in memento mori.

The god of wine stares out at passersby on this busy Pittsburgh thoroughfare.

An incredibly well-preserved piece of ninth-century Viking poop.

The one-time stronghold of the noble Douglas family, now home to ghost sightings and nesting birds.

Ruined castle with subterranean vaulted Goblin Ha' or "Goblin Hall."

This 13th century castle is chock full of ghosts and impossibly rare cows.

These upturned herring boats make nifty storage sheds for fishing goods.

Twice a day this ancient path disappears with the tides, leaving the Holy Island of Lindisfarne out to sea.

This enchanting Victorian estate was home to the world's first hydroelectric power generator.

This enormous secondhand bookstore inside a Victorian train station sparked the "Keep Calm and Carry On" craze.

It's possible to walk inside one of the largest Neolithic tombs in Britain.

Britain's tallest megalith towers over the cemetery of a quiet English village.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

Where America’s first doomsday cult awaited the end of the world.

A portrait of the Charter Oak hangs in a frame made from the Charter Oak.

Legend says this little-known stone circle is formed from people petrified as punishment for dancing on the Sabbath.

This ruined medieval castle was the scene of Lord Robert Dudley’s seductive reception for Queen Elizabeth I.

A park full of outsider art, created by college students studying outsider art.

The final resting place of two members of the infamous Doan gang, notorious outlaws and Revolutionary War Loyalists.