An absolutely beautiful 200-foot stained glass installation traces the evolution of knowledge.

This 15-foot tall obelisk commemorating the Philadelphia-Baltimore railroad connection sat neglected for over a century.

The oldest surviving presidential residence in the United States.

One of Philadelphia's largest murals resides hidden under this bridge.

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

The world's third-largest crystal sphere has sat in the Penn Museum since 1927 with the exception of one outlandish theft.

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

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

This museum boasts a bucket of teeth and tells the tale of a 20th-century dental circus.

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

Instruments, apparatus, and rare books all relating to chemistry and its related sciences.

Yo, Adrian!

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

Dr Barnes' $25 billion private collection of art and arboretum.

This meticulously extracted nervous system allegedly came from a 19th-century custodian who donated her body to science.

This Philly cemetery is the eternal home of many famous area residents, including Rocky Balboa's wife.

The origin of this mechanical boy was a mystery until he revealed his maker by writing it in perfect cursive.

Enjoy a slice while browsing the world's largest collection of pizza memorabilia.

The oldest surviving botanic garden in the United States.

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

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

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

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

A layered tribute to the work of mosaicist Isaiah Zagar.