13-15 must be with their legal parent or guardian every visit. 16-17 can have their own standard membership, but a parent must sign them up their first visit. Otherwise, they must come with their parent as a guest
When I joined I was 13, But you need at least one of your parents with you until you are 16. However, at 18 you can pay for your own account.
Apparently 15, judging from the loud MTV they pump in to the place. Sorry I can't offer a more definitive response.
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