If you want Halloween scary it is the park only side but scary. That is October. My family goes for the weekend of father's day. It's al open, not overly crowded
June is when we go. Not many people
If you want to visit while the water park is open you will have to be at the park in its prime time. Memorial to labor day. If not and you just want to do the park side of like as early as mother's day is actually a lot of fun and not very crowded either.
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