Original 1st printing 14&1/8 x 19&7/8" concert poster for the Sir Douglas Quintet plus Big Brother & the Holding Company (featuring Janis Joplin) and "a Special Surprize Visit"* appearing at the Avalon Ballroom in San Francisco, CA on 10/15-16/1966. Art by Stanley Mouse and Alton Kelley with a photo by Edward Steichen (Gloria Swanson, 1924), image is # 30 in the Family Dog/Avalon series. Medium vellum stock poster is in absolutely GORGEOUS mint/near mint (A/A-) condition; maybe there's a debatable edge/margin ding or perhaps a stray pinch ding, but I can not see anything with my naked eye- it's THAT crisp/bright. The "Surprize Visit"* alluded to above was by none other than the 13th Floor Elevators, making this FD anniversary celebration an all-Texan-fronted affair... not to mention the ad-hoc jam fronted by Jerry Garcia and Pigpen on the 16th (as mentioned in "Mojo Navigator"*). 

http://lostlivedead.blogspot.com/2009/07/october-15-1966-avalon-san-francisco-ca.html