I just read this "Phables" from October via a link from the Sheldon blog.

Man, the strip really brings back memories. I've visited Philly twice, and both times I've accidentally taken the Ben Franklin to Camden. The first time I became quite upset by there not being a quick and easy way back onto the bridge, then surprised by the toll. Five years later on my second visit, I knew I was in trouble when I got stuck heading onto the bridge, but at least I knew where to turn around at and I knew about the toll this time.

I always love my visits to Philly, maybe if I visit more often I'll figure out how to get off I-95N without visiting Camden.