I used to live there. I have been through Riverside and it is ok and about 15 minutes from Williamsport. I have stayed at Shangri-La, which is about 1/2 hour and it is really nice. Very clean, friendly and nice facilities. If you have any further questions about the area, feel free to PM me. My family all still lives there. Are you going for Little League World Series by chance?
Husband, myself, 15 yo daughter, 13 yo son, 11 yo daughter,4 yo black lab named Boomer, 1 yo black lab mix rescue, Murphy and the newest edition...a 4 month old blind smooth coat collie named Toby!
We just got back from the KOA Williamsport South/Nittany Mountain. Nice, shady sites (we were in #13, seemed ideal) along with a pool, firetruck rides for the kids, playground, fishing pond, etc. Greatly enjoyed it. The site: