In short, taking an RV here is not recommended. While some of the campsites could probably fit a vehicle that large, I wouldn't recommend taking one there. Especially if it's your first time driving one. The road that takes you over the mountain to get to the campground from Riverton is narrow and not entirely paved and the road from the west side of the mountain isn't paved either. There are many large pot-holes and tight switchbacks. The campground is better suited for tent camping over RV camping in my opinion and definitely more easily accessed by cars/trucks. Someone who came with me when I went this past Labor Day weekend drove a Honda Insight and had little trouble making the drive.
I saw some small RVs in the dispersed camping nearby, but definitely agree about the narrow roads with potholes! If you do, definitely come from the Whitmer side instead of up and back down the mountain. No electricity here. I think maybe the Seneca campground is a better option.
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