The oldest continually operating golf course in the United States.

An unusual and eclectic collection of local historical memorabilia.

An eccentric priest's tribute to George Washington, this chapel tells the story of the American Revolution.

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

South Philadelphia is home to Keith Haring's only surviving in situ collaborative public mural.

Overshadowed by quilts, the artistry of these patterned textiles went underappreciated for too long.

This spot memorializes one of the greatest plays in NFL history, unless you happen to be a Raiders fan.

A rock maze opens up to a panoramic viewpoint at an abandoned mine full of ghost stories.

The legacy of baseball great Roberto Clemente is preserved in a retired Pittsburgh fire station.

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

The graffitied ruins stand hidden within the Pennsylvania woods.

Penn State's giant bug collection.

"Where the ducks walk on fish."

Memorializing an American tragedy of massive proportions.

The Cold War-era "underground Pentagon" is a sprawling subterranean hideaway for the Defense Department.

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

Golden and naked, the figure that was once the highest point in New York is all that remains of the second Madison Square Garden.

A planned settlement in Pennsylvania once housed the aristocratic refugees of the French Revolution.

An Irish Memorial commemorating those who perished due to potato blight.

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

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

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

The sounds of the world's largest fully functioning pipe organ dazzle shoppers at a Philadelphia Macy's.

Current docking place of the SS United States, the fastest transatlantic ocean liner.