An eccentric priest's tribute to George Washington, this chapel tells the story of the American Revolution.

The souvenir got the company’s founder out of a pretty pickle at the World’s Fair.

This 19th century machine put animals (including humans) in boxes to study how they metabolized calories.

Color-coded signs direct drivers on a network of routes designed to avoid Pittsburgh traffic.

The abandoned coal loading dock is a canvas for unsanctioned art.

The site of America's first commercial oil well essentially disappeared after the town went bust.

A rock maze opens up to a panoramic viewpoint at an abandoned mine full of ghost stories.

This public space is speckled with the eerie remnants of a defunct amusement park.

This spot memorializes one of the greatest plays in NFL history, unless you happen to be a Raiders fan.

An Olympic hero stripped of his medals is buried in a town he never visited, which took his name after his death.

Locals call this magical moss-covered walkway the "Emerald Path."

A soon-to-be-forgotten roadside spectacle loaded with local lore.

Dozens upon dozens of boulders engraved with scripture tell the story of one man's troubled life.

A hidden piece of Altoona's railroad history in a long-forgotten abandoned town.

A quirky collection of outsider art made from automobile parts.

A preserved 18th century homestead in Western Pennsylvania marks the spot where the Whiskey Rebellion began.

This colonial mansion has been home to a staggering number of American historic figures.

A diorama of the Civil War, fought by cats.

A small museum along the Susquehanna River is home to a rich collection of Native American artifacts.

Contrary to popular belief, this secluded statue doesn't represent Pennsylvania's founder.

Where the oil industry began.

The Cold War-era "underground Pentagon" is a sprawling subterranean hideaway for the Defense Department.

Pittsburgh's literal underground railroad.

A living maritime paradox still floats in the same lake where it was built and resurrected... or was it?