The park opens at 10am-10pm but Hershey world opens at 9am
10 am but I believe if you're a season pass holder it opens at 9am
The park has early admission for season pass holders which is 9am. Regular entry is 10am, you can bring in water but it has to be closed, plastic and in a bag when you go through security at the bag check line for the park.
I believe 10am, also someone had asked if you could bring in water and you cannot
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