Halloween is obviously Friday. You don't need BBG's advice on this, but be careful, designate a driver etc.
More details to arrive at a later point in time, but The Brewer's Art will have a Holiday Beer Tasting event on December 6 from noon to 4 pm. Also, according to their website the Seven Beauties Rye and Cerberus Tripel are currently the seasonals on tap.
There will be a pair of beer tastings at The Perfect Pour in Columbia. On Friday to celebrate Halloween from 3-8 pm they will pour Coney Island Freaktoberfest, Wychcraft and Rogue Dead Guy Ale. On Saturday from 3-7 pm they'll transition to Thanksgiving and pour Weyerbacher Imperial Pumpkin and Ace Ciders.
Finally, be sure to check the Halloween beer specials page here at BBG and email in tips if you know of anything else going on. For example, just in the inbox today I've been informed DuClaw will be pouring its "31" spiced Munich Dunkel on Halloween until supplies last.
4 hours ago