Phillyfag here, I've been all over Pennsylvania. Pine Creek Gorge is fuckin great and can be an intense place for backpacking/survival. I go up fairly regularly.
Get a map at the visitor center at Leonard Harrison State Park overlook (you can just leave your car there. I've done it about a dozen times for days at a time and not once had an issue) and head down the "Turkey Path." This is all heavily tourist.
https://maps.google.com/maps?hl=en&tab=ilOnce you reach the bottom there's a gravel path for bikers/dayhikers that runs a good length on that side of the canyon. This is the tourist side. The other side of the canyon is steep and treacherous, and wild for the most part. There are places with private cabins and hiking trails though, so check your map and make sure your crossing into a nice expanse of wilderness.
Once you find a good place to cross, you need to wade/swim across the creek. Its a good sized body of water, so you need to find a good spot to cross so get creative. Once on the other side you'll have to climb a very, very steep canyon wall. Difficulty varies, but I've never had an easy time getting up, and often have gotten into dangerous situations.
You can follow some streams that run into Pine Creek up the canyon - a plus to this is that you will find huge, beautiful waterfalls and limestone cliffs. Downside is that you have to climb over them. Seriously, if you're new to this shit don't even try to climb up them or you will be dead. Either way though, go check out those waterfalls. Only a few people even know they exist, and the funny part is they're more impressive than anything in the tourist areas.
Anyway, if you chose a good spot to climb up the canyon wall, once you get up you will have both: a fucking fantastic view of the canyon, and a huge area of wilderness to explore.
Pic is me climbing the canyon. Actually much steeper than the camera angle suggests. I'll dump some more pictures if u guys want.