These disused steel furnaces are now haunting ruins that may one day be a national park.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

This park contains a number of standing stones meant to heal and inspire.

Once the "Eighth Wonder of the World," this iron railroad bridge was decimated by a tornado.

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

According to local myth this cemetery is half evil spirits, half good—split down the middle.

This stately 19th century library pushed architectural boundaries at a time when the public library movement was just taking off.

Yo, Adrian!

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

True to his word, George Swanson is buried in his white 1984 Corvette.

The famous bell was secreted away and hidden in a church in Allentown during the British occupation of Philadelphia.

This historic Pittsburgh tennis complex is a rare example of natural red clay courts.

No one knows who painted this mysterious mural in a Penn State basement.

A larger-than-life statue of America's favorite sundae marks the place it was invented.

Journey through a collection of over 35,000 Halloween items from all generations.

A daily replay of the experiment that proved the rotation of the Earth.

The Pennsylvania landscape depicted by a quarter mile of mosaics made from used road signs.

Sections of the iconic limestone columns have been left uncleaned as a reminder of the city's polluted past.

Could it have picked a better place to land?

Once on display alongside a giant Gumby, it’s as tall as a nine-story building when fully extended.

The humble field where the first Major League Baseball game was played.

The residents of this ominous-sounding street in Pennsylvania liked its name so much they fought to keep it.

America's first serial killer rests in anonymity.

Its vintage camera collection gives a snapshot of the past as viewed through a photographic lens.