The last of Philadelphia's wood-paved streets is now a landmark of terrible engineering.

Step into a pastel time capsule where candy is truly dandy.

America's smallest national park site is the former residence of exiled Polish national hero Thaddeus Kosciuszko.

A daily replay of the experiment that proved the rotation of the Earth.

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

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

Yo, Adrian!

Ant sculptures march up the side of what used to be an iconic spot in punk rock lore.

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

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

A layered tribute to the work of mosaicist Isaiah Zagar.

An abandoned cemetery lies in ruins as the surrounding forest swallows it whole.

America's most famous museum of medical oddities is home to the remains of Albert Einstein's brain.

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