At the door only, unless you have a group. $6 adults, $4 children over 4, under 4 is free. There is a transaction fee for all credit and debit cards.
You can buy at the front desk.
You can check online but fairly certain its there only and they do give some discounts.
You can buy on line.
Go early and there's no line
I went a few weeks ago and I bought them at the door it was 10$ per adult and its worth it. Its an awesome place to visit. You cant use a camera on the bottom floor but you can on the second floor
At the door.
It is OK at the site.
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