We stayed at Pine Grove Furnace State Park over the 4th of July weekend and had a great time.
We had an electric-only site. The sites are spacious and not too close to each other. Each site has a tent platform as well as an area for a camper. We were close to the bathroom-only building (there is another building with showers and toilets).
Two hints if you stay here:
1) When entering the campground, there is a sign that says all campers must stop and check in - there doesn't seem to be way to check in.
2) Firewood can be purchased from the camp host (we bought ours from the general store and carried it back).
We stayed here in a Tear Drop Trailer.