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

Hidden behind West Philadelphia rowhomes is a haven for migratory and local bird species both ordinary and rare.

The abandoned coal loading dock is a canvas for unsanctioned art.

Contrary to popular belief, this secluded statue doesn't represent Pennsylvania's founder.

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.

The oldest surviving botanic garden in the United States.

In the early 1800s, surgery was also a show.

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

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

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

Huge masonic hall in Philadelphia with lavishly themed rooms.

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

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

A layered tribute to the work of mosaicist Isaiah Zagar.

These whimsical works of art tell the story of the city's past and present.

A more than 260-year-old crypt built on Boston's oldest English burial ground.

The former site of an all-but-forgotten colonial landmark is now remembered by an often overlooked bas relief.

An interesting decoration on this historic site, this weathervane comes with as many legends as it does questions.

Tragedy on Little Brewster Island memorialized.

One of the indelible moments of the American Revolution took place at this location.

Statue commemorating the use of ether in anesthesia.

The oldest working bell set in North America, the bells at Old North Church sat silent for their first four years in Massachusetts.

The remnants of a Gilded Age elegance preserved in the middle of a stark modern tower.