At most KOAs, the tent sites aren't fully occupied. The RV spots are what sell out. Having said that, you might find availability problems in season on weekends to be difficult, especially if you want more than one. Book on KOA.com as soon as you plan. The cancellation is only one night, which is minimal for rent sites.
Availability varies always best to make a reservation as early as possible. Once you figure out what days you want to be there I'd make a reservation. You c as n reserve online at koa.com too.
I would call the park , they would have a better idea on availability then
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