There are 2 types of tickets one does one doesn't.
Each park has its own ticket. There is a combo pack, but, you to show separate entrance passes.
You can visit the zoo with zoombezi bay ticket but NOT vise versa
Zoombezibay ticket gets you into the zoo too but a zoo ticket doesn't get you into Zoombezibay
If you enter the zoo with your waterpark ticket then you can still see the zoo with only the waterpark pass. At least they let us do that, not sure if that's how it's meant to work. However I will say that it rained our first day and we had bought the waterpark pass so we only got to see the zoo.
Separate passed are required but can be purchased together
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