It's hard to say because it's all first come first served. I would say get there as early in the morning as possible (6-7am). I'll usually do a couple laps on the road checking all 3 campgrounds for open spaces. Most times you'll either see someone packing up or they'll just see you and let you know they're leaving.
Early arrival is definitely best. Mccabe flat camp areas, about 3 miles in fron 140 , near sandy beach area is best.
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