Original 1st printing (blue background (*there is also a gray background version) 16&7/8" square (diamond-shaped) concert poster for the Grateful Dead appearing with the Charles Lloyd Quartet and the Mystery Trend at the Rock Garden in San Francisco, CA from 3/28-4/2/1967 (dates are hand-altered on the poster).
Art by Michael Wood/Pyxis Studios, image is featured in the Art of Rock book on page 196 (plate 2.212).
Medium-thick flat vellum stock poster is in good to very good (B to B/B+) condition; tack holes, light creasing and a couple of tiny wedge-shaped drag pulls in the corner tips, a series of light handling dings/tiny stress creases scattered around the outer margin and within the image area, the aforementioned hand-corrected dates (written in black pen) and a few very well-camouflaged pin-prick surface stains, otherwise fine.
Uncommon early Grateful Dead poster from a VERY short-lived and semi-obscure San Francisco venue. For the interesting back story (along with equally fascinating commentary), read HERE: