This spectacular public market has got meat, fish, vegetables, baked goods, and enough kielbasa for a lifetime.

Funded by John D. Rockefeller, this is one of the earliest, and most beautiful, shopping arcades in America.

Marvel at this turn-of-the-century masterpiece that has been turned into a rather stately supermarket.

This dramatic rail curve was once the target of a failed Nazi attack.

The site of America's first commercial oil well essentially disappeared after the town went bust.

Memorializing an American tragedy of massive proportions.

Steepest flood safety railway in the entire world.

A well-preserved relic of the industrial age steel and iron works that dotted West Virginia.

An American flag was erected for every day that passed during the Iranian Hostage Crisis.

The largest burial mound in the United States holds the remains of prehistoric West Virginians.

The house that Frank Lloyd Wright "(shook) out of his sleeve at will" at the age of 86.

Frank Lloyd Wright's most iconic home dangles over a Pennsylvania waterfall.

Despite its lavish ornamentation, and wholesome lifestyle of its devotees, this mountain commune has faced its share of issues.

This shrine to McDonalds' most iconic sandwich holds a 14-foot tall burger.

A retrofuturistic art installation in the Pittsburgh Airport.

House of vintage taxidermy and Steampunk sculptures in a quiet Pittsburgh neighborhood.

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

The last street in Pittsburgh that's paved with wood.

One of the steepest streets in the United States makes an intriguing challenge for cyclists.

Mutant vegetables, transgenic mosquitos, and atomic rodents span the walls of this one-of-a-kind museum.

Within this beautiful Pittsburgh cemetery, a unique headstone bears witness to one man's eternal love for Jaws.

Once the most painted on object in the world, this short campus fence is well on its way to being so again.

This Old Testament garden features 100 plants from biblical times.

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