It's an amusement park, but it's more embellished with some accumulated imagery
The water park is an add-on, so if you buy a one day ticket you would need to do both on the same day. We spread it over two, but it possible to do both in one (long) day
You have to go through the park to get to the water park. So technically yes but as far as I know you can't buy a ticket just for the water park.
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