One day
We only do 1 day and can enjoy most of it. I have 4 kids as well.
One day is good. Much more family friendly than 6 flags
You can see it in one day. But there is a lot to do in Hershey so you could stay. Go to a Bears Game!
You can enjoy the park comfortably, without rushing, in one day. I've been there many times and have only seen it uncomfortably busy once.
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