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

These beautiful ruins deep in the Pennsylvania woods are thought to have been a ski lodge or a speakeasy, but no one really knows.

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

A tour de force of a fountain, memorializing a man who loved fountains more than anything else.

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

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

Priceless space junk on display in front of a local Dairy Queen.

The first American axe throwing club.

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

Yo, Adrian!

Where America's first doomsday cult awaited the end of the world.

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

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

This elaborate towering structure was once famed for its revolutionary height.

Erected in 1697 this Philadelphia bridge is the oldest surviving roadway bridge and perhaps the oldest stone bridge in the United States.

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

This stone tower marks a lookout point over the historic Washington Crossing, and maybe some buried treasure.

An almost life-sized elephant named Ms. Ellie greets visitors at this jumbo-themed museum.

Philadelphia boasts one of the best — and most often overlooked — traditional Japanese gardens in North America.

The mortal remains of a Russian prince, priest and paranormal investigator who came to America in 1792.

A local prank turned town icon.

A park full of outsider art, created by college students studying outsider art.

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

This might just be the TARDIS of bookstores.