This beautiful stone arch bridge wasn't even expected to stand for one day, but people have been crossing it for centuries.

Pennsylvania's highest point is spotted with boulders which were pushed to the surface by nothing but cold.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

This original Mason-Dixon line cairn placed in the 1760s was put in the wrong location because of the gravitational pull of the Allegheny Mountains.

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

The site of the little-known Pennsylvania battle that sparked the Seven Years' War.

The penultimate and final resting places of British General Edward Braddock—minus a few bits and pieces.

This historic furnace was once used to produce cannonballs during the Civil War.

A miniature golf course crafted inside the world's largest simulated cave.

A macabre farm reserved part of its 222-acres for dead bodies, all in the name of science.

A neighborhood of houses made of poured concrete through a process invented by Thomas Edison.

Each step is a mere four inches tall, said to be measured by the stride of a woman wearing a hobble skirt.

A museum commemorating the Donora Smog, which killed 20 people in October 1948 and sparked national outrage over air pollution.

One man's real life disfigurement inspired a lasting local legend surrounding an eerie tunnel.

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

The pop art icon's gravesite is broadcast 24 hours a day on his museum's website.

Where the "World Pinball Champion” is crowned.

It may appear to be a fancy junk yard, but each item has a story to tell and a lesson to impart.

A stone arch leads to a cavernous 1930s spring house tucked away in the Pennsylvania woods.

Could it have picked a better place to land?

Hidden in the hills of Western Pennsylvania lies one of the best-kept ghost towns in America that you can legally visit.

The only museum in the Western Pennsylvania region that focuses on Asian art and Meissen porcelain.

An otherwise quiet campground becomes a bustling medieval town for two weeks every year.

The aggressively banal name of this underground fortress of bureaucracy does little to evoke its truly surreal existence.