Probably just depends on the size of the individual site. I think there is a 7-8 person, 2 car max per site. It would say on their website.
You must call and ask.
I haven't seen more than 3 in the (almost) 40 years I've been going there. Always call and ask first.
I have seen up to three tents in one site. I don't know if they charge extra for them though
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