Alabama has a fiberglass Stonehenge. With apologies to Spinal Tap, this one is full-size.

An immersive environment that is part haunted house, part choose-your-own-adventure, and part jungle gym.

A cabin completely covered in coffee mugs, where visitors are welcome to leave one of their own—if they can find an empty nail.

A humble garage, world-famous for being the epicenter of a technology revolution.

A spiritual retreat in the heart of Los Angeles offers stunning gardens and a labyrinth to lose yourself in.

A sewing machine tycoon built this miniature castle for the people and to beautify a lakeshore.

Hidden for 165 years inside a building designed by Thomas Jefferson are the remains of what may be America's first educational chemistry lab.

An abandoned early-20th-century boomtown sits within the Calico Rock city limits.

This overgrown Illinois water park offers a whole new type of adventure.

The oldest living tree in Manhattan comes shrouded in sinister legend.

A local prank turned town icon.

Collection of trolley cars in the woods represent one man's attempt to preserve transportation history.

Sweet or salty, super hot or mixed into beer, this is the holy land for all things licorice.

The oldest licensed distillery in Ireland.

Near Birmingham, England three and a half miles of top-secret tunnels housed a World War II “shadow factory” and a Cold War nuclear bunker.

A gothic palace of endless stalagmites and pseudoscorpions waits within one of the world's most beautiful caves.

This one-room schoolhouse in rural Arkansas dates to the 1920s, but looks like it could be the 1820s.

A small island abbey is the final resting place of many medieval Scottish monarchs, including the real Macbeth.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

A planned settlement in Pennsylvania once housed the aristocratic refugees of the French Revolution.

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

The remains of one of America's first radiation testing grounds still rest ominously in a Georgia forest.

What better place to take a seat?

Bad farming practices caused this unnatural natural wonder.