There are a lot of good additions to this thread!
I've been to both Chester and Camden, and needless to say, they're both horrible. Besides the aquarium in Camden, but still....
Chester, PA was booming in the 40s-50s and manufactured Ships, trains and even pianos. Similar to what happened in Detroit, now it has some of the biggest unemployment and drug addiction in the country.
This is a pic I found on the Internet of Chester and it actually looks pretty good here.... not sarcastic.
Camden has the highest crime rate in the country since 2008: