It would take 35 firetrucks to fill this enormous glacial pothole.

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

Board a mine car and descend the #190 slope 300 feet underground into the Clark Vein of coal.

America's first serial killer rests in anonymity.

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

Pennsylvania's own Roswell-style UFO mystery.

An outlandish shoe shaped house built by an eccentric millionaire.

This lush forest valley was once mined for lumber to the extent that it was once nicknamed "The Pennsylvania Desert."

This Pennsylvania cave holds evidence of the oldest known inhabitants of North America.

This museum boasts a bucket of teeth and tells the tale of a 20th-century dental circus.

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

Pennsylvanian mass grave and possibly mass murder.

This titanic java kettle is one of the many kitschy landmarks located along America's OTHER famous highway.

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

There aren't too many operational funiculars around, but Pittsburgh has two!

Yo, Adrian!

The oldest farmer's market in America is so ancient it was approved by the King of England.

This meticulously extracted nervous system allegedly came from a 19th-century custodian who donated her body to science.

The internal railway of one of the biggest steel plants in America has been transformed into a linear park with unique industrial views.

This Old Testament garden features 100 plants from biblical times.

The first American department store, and home to the largest operating musical instrument in the world.

This palatial botanical garden is home to one of the largest pipe organs ever installed in a private residence, and a piece of Wood's cycad.

A clone-tree in Washington Square Park sprung from seeds that went to the Moon and back.

Over 100 concrete munitions bunkers are all that remain of a Pennsylvanian village seized by the US government.