Original 1st printing 5&1/2 x 8&1/2" concert handbill for NYC folk/blues/rock legends the Blues Project (featuring Al Kooper) appearing with the Great Society (featuring Grace Slick) at the Avalon Ballroom in San Francisco, CA from 4/22-23/1966.
Art by Wes Wilson, image is # 5 in the Family Dog/Avalon series (OHB-B in the Eric King Guide). This was the first Family Dog show held at the Avalon.
Thin flat stock handbill is in good/decent (B/B-) condition; there are a set of horizontal/vertical folds/creases, a set of tack holes, a bit of toning, a couple of tiny surface scuffs here and there, but the real main issue with this example is the extensive amount of hand-writing on the reverse- rendered in red and black pen, this obviously very personal letter goes into a couple of interesting details of the then-current SF music scene, specifically in relation to a particular band that the author had experience dealing with... a REALLY wild read, to say the least (see photo)... there are also a pair of small pulls and clear tape remnants on the reverse, but the letter is really what makes this example more unique than virtually any others I have seen.
A FASCINATING 1966 Haight-Ashbury scene artifact, to say the least.