Original 1st printing 14&1/4 (appx.- the right side is irregularly cut on every one of these) x 20&1/2" concert poster for Canned Heat (Blues Band) with Big Brother & the Holding Company (featuring Janis Joplin) at the Avalon Ballroom in San Francisco, CA on 6/8-11/1967. Art by Rick Griffin, image ("Magic Show") is # 65 in the Family Dog/Avalon series. Medium flat index stock poster is in ultra-crisp near mint (A- to A-/B+) condition; just a trace of edge/surface wear (a couple of tiny dings and a sliver of dirt/smudging in the extreme left margin and a tiny stray pinch/corner ding or two, otherwise it's an absolutely GORGEOUS-looking 1st printing/white-border version of this somewhat controversial early Rick Griffin image from the Avalon.