Forget Pat or Geno's, they both suck in my opinion. Hit up Tony Luke's on Front and Oregon. If you don't want a cheese steak try a pork sandwich, extra wet, with mushrooms and mild provolone. Catch a Phillies game if they're in town this weekend. They suck, but the park has been deemed HR haven, and it's a nice stadium. They have a place called the Bull Pit or something like that, named after one of the players. It's bbq food. The guy was signing autographs. I didn't know who he was so said rather loudly "Who's the ass clown holding up the line?" He heard me, and didn't appreciate it, but we got a laugh when we saw how pissed he was.
Have fun. There's a lot of history in Philly. Birthplace of freedom. Was the capital of the US. The USMC was founded in a tavern in Philly.