jackrobinryan is right, there aren't many campgrounds around Pittsburgh. In addition to Mountaintop in Tarentum, there is a KOA about 30 miles south of the 'Burgh in Washington, PA. It's been a couple of years since we stayed there. The sites aren't real big, there are some permanently parked RVs, and it's noisy because it's right at the intersection of I-70 and I-79, but it's relatively easy to get around via I-79.
There is also Rose Point Campground about 50 miles north of downtown in New Castle, PA. We haven't stayed there for several year either; but, in spite of being farther from downtown, it was a nicer campground. It's far from downtown; but we used to live in the North Hills of Pittsburgh, so that's where our doctors and family were.
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