Definitely varies by event. Check their website before arriving. Many if not most shows are all ages, however the bar is always open even on an all ages event. At such events, if under 21 (or even anyone visibly 21+ without an government issued ID or passport), security staff will mark you with a big ol' "X" on both hands: no ins-and-outs and no alcohol. 21+'ers get a wristband, otherwise.
Varies by event
As far as I know you must be 21 or older for most/all events. As for children, it would depend on the event
I believe so yes. Or at least over 6 years old.
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