No, you do *not* need to be 21, and you do *not* need to accompanied if you are under 21. Table seating in the biergarten is open to any age (of course, you must be 21 to sit at the bar).
Unaccompanied minors would probably not be allowed.
No. Probably need to be with someone 21 or older but we were there with a 13 year old.
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