I went in July and thank God I purchased my tickets online cause at 9.30 am, they were not allowing anyone at the gate since they had already reached capacity.
Yes you can purchase a ticket at the gate
From what i understand you park in the garage and buy your ticket. Then a bus takes u to the drop off area for the park and u walk the rest of the way to Volcano Bay. U should be able to get a ticket at volcano bay but im not sure.
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