Both although personly i would choose in person since when i got mine online they said they lost it so i would perfer in person but its your choice in the end.
I think you can buy them at the door
While you can buy it in person or online, I really do suggest online since the wait can take so long. If you buy it online, you save the pass to your phone and skip the line & enter through the season pass entrance on the side. Easy Peasy.
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