There is the Nason Creek campground on the way to Lake Wenatchee. I believe some are reservable and some are FCFS. They are a short bike ride (1/4 mile) from Lake Wenatchee.
When ee were there last week, one of the rangers gave us a map of the area, these are some of the camgrounds it shows; Hidden Lake, Camp Zanika, and a YMCA camp
Look up fish lake loft if you don't mind cabins
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