Original 1st printing 14 x 21" concert poster for 1960's UK folk-rock duo the Incredible String Band appearing at the Fillmore West in San Francisco, CA on 5/11 and 5/13/1970.
Designer unknown, image is # 232-A in the Bill Graham/Fillmore series (these shows fall in between the BG 232 and 233 shows).
Medium-thick flat index stock poster is in absolutely STUNNING mint/near mint to near mint (A/A- to A-) condition; there is a tiny black spot in the lower left corner (may be part of the printing) and there MAY be a soft pinch bend or two hiding within the image area, but you'd be pretty hard-pressed to find a cleaner example.
GORGEOUS specimen of one of the more difficult-to-obtain ISB posters from the Fillmore series.