You must be 21+ to enter, as is the case with most nightclubs in Chicago. Concert venues like Metro, The Vic, Aragon Ballroom, etc. are able to host 18+ or All Ages events, however.
No, unfortunately they card at the door rather than at the bar. It may be worth calling them ahead of time and seeing if they can mark your hands or something, so the bartenders know not to serve you (some venues will agree to this), but I wouldn't bet on it.
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