I'm getting the PT and the SRT confused. The SRT runs down past NTown, not the PT. We usually start from the Oaks, PA parking lot and ride down to Norristown, Conshohocken or Manayunk. So I think that might be the Schuylkill (it runs along the river... duh kimmy). The Perkiomen Trail is more packed gravel (though there are paved sections?) and runs Trooper/Collegeville type area up to Schwenksville and Spring Mountain and such. It's a nice ride on a bike with knobbies (the gravel in sections gets a bit much for a bike with slicks on it) so if you're looking for a different ride that's a bit less crowded some weekend, check it out.

Perkiomen Trail info