Original 1st printing 14 x 20" concert poster for  Big Brother & the Holding Company (featuring Janis Joplin) appearing with Mount Rushmore at the Avalon Ballroom in San Francisco, CA from 11/23-25/1967.

 Art by Joe Gomez, image is # 93 in the Family Dog/Avalon series.

 Medium flat index stock poster is in near mint (A-) condition; maybe there's a tiny edge ding/pinch bend or two hiding somewhere, but for the most part this example looks pretty much like it just rolled off the press yesterday. 

Check out Joe working on the poster in 1967!