This Philly landmark has a giant butterfly pavilion, three floors of insect displays, and withstood a $40,000 heist.

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

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

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

The residents of the Neighborhood of Make-Believe live without much fanfare within the Pittsburgh Children's Museum.

America's first serial killer rests in anonymity.

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

A historic covered bridge is but one example of an oddly prevalent American urban legend.

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

The ruined remains of a coal mining ghost town are hidden within the woods.

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

Yo, Adrian!

This little-known Revolutionary War fort is supposedly haunted by the ghosts of its past.

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

When the Austin Dam failed it destroyed much of Austin...and then it failed again.

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

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

In the early 1800s, surgery was also a show.

The only way to see Pittsburgh is from the top of this lookout point, just like the ancient members of the native peoples did.

A failed piece of Orientalism has become the proud symbol of a community.

This hidden gem of a garden has one of the only surviving Victorian ferneries in America.

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

The remains of a community that was forced to move for a dam that never materialized still rot in this Pennsylvania park.

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