Kadism North Side Philly!
It is alleged by many that Graffit as we now it 1st started in Philly before New York. Here is a 2010 documentary on the history of graffiti in Philadelphia, featuring interviews with Cool Earl, Kool Klepto Kidd, Johnski, Notorious BIK, MB, Kair, former mayor Wilson Goode, Jane Golden, and many more.
Sly Artistic City - Philly Graffiti History
For more info on Philly Graffiti check out http://phillygraff.blogspot.com