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

The home and studio of a visionary woodworker now stands as a museum and example of his artistic genius.

This charming colonial alleyway is one of the oldest continuously used residential streets in the U.S.

The largest university building in the West is a gothic masterpiece containing dozens of theme rooms based on different countries.

A museum dedicated to the strange and extravagant costumes and memorabilia of the mummers, a tradition older than Philadelphia itself.

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

This church in Pittsburgh is home to the largest collection of religious relics in North America.

The universally beloved children's television figure is interred on a high hilltop in one of western Pennsylvania's oldest cemeteries.

These tourist trap caverns are said to be the former home of a legendary Pennsylvania Hermit.

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

This might just be the TARDIS of bookstores.

This little-known collection holds everything from "Dracula" notes, to the manuscript of "Ulysses," to the forged works of Shakespeare.

This little museum in the town where zombies were born celebrates the living dead.

Delicate Wurlitzers, creepy clowns, and The Noid all share space in this insane explosion of kitsch history.

The taxidermied remains of Charles Dickens' pet raven, which helped inspire one of Edgar Allan Poe's most famous poems.

Eccentric concrete mansion and museum designed and built by hand from the inside out.

Mural made of 100,000 pieces of hand blown glass, and until recently, the largest glass mural in the US.

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

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

Tour the dark and beloved poet's former cobwebbed basement, which may have inspired "The Black Cat."

A rare view of a preserved Victorian science museum.

Mysterious rocks that ring musically when struck.

World's first "penitentiary," meant to be humane, drove men insane.

What was once the largest mine in North America has left behind a hollow hill filled with bright blue waters.