Re: Appalachian Trail and trout fishing
What Rip said. You can hike there, and fish, just don't expect to get very far.
Also, last time I checked, PA law for hiking the AT on State land was weird. Essentially you could only hike one way and stay overnight. So you could have a 60 mile trip planned and stop and points A, B, and C and be legal. But if you wanted to hike back it would be illegal.
This was a number of years ago and may have changed by now, but it is something that you should look into.