On the same day that a full page ad announced mail order ticket sales for four Led Zeppelin concerts in Chicago news broke that drummer John Bonham was found dead. The shows were cancelled and the tickets were never distributed. Many years later they were secured and offered to collectors. Here's a set of six different color tickets designating different sections of the venue for these cancelled but still historic shows. Tickets are NM. Four are for Nov. 12th, two for Nov 15th.