During the summer of 1970, Bill Graham presented an extraordinary series of concerts at Tanglewood, the renowned classical music venue located in the scenic Berkshire Hills of western Massachusetts. At the time, presenting rock music in a classical venue was a surprising and precarious step to take. To many, hearing The Fillmore and Tanglewood in the same sentence equated to "when worlds collide." Much like his approach at the Fillmores, Graham's "Fillmore at Tanglewood" series presented diverse handpicked triple bills, but with the added advantage of a beautiful open-air venue and plenty of informal lawn seating. With the Fillmore East crew providing technical support, these concerts would be hailed as a technical and artistic triumph and would entertain the largest Tanglewood audiences to date. In a year plentiful in memorable concerts, these Tanglewood performances truly stand out. Jethro Tull and The Who, which opened the 1970 series on July 7th, and Miles Davis and Santana, who closed on August 18th, all delivered outstanding performances that rank with the most inspired of their careers. Bill Graham presented another equally memorable night at Tanglewood right between those two concerts. On that evening, July 21, 1970, he again presented a group at a pinnacle moment in their career. However, this concert would present the promoter with serious challenges and has a history all its own. Graham originally intended on presenting Joe Cocker and his extravagant Mad Dogs And Englishman revue, literally the biggest rock act touring in 1970. Cocker was booked and advertised, but the demanding logistics of that tour and his deteriorating health brought a premature and permanent demise to the whole endeavor. Without a band, Cocker was forced to back out just weeks before the gig, leaving Graham without a headliner. During the set break between Jethro Tull and The Who on July 7th, Graham announced Cocker's cancellation. He also greatly enticed the audience and media present by stating that he was 90% certain that Jimi Hendrix would be replacing Cocker as the July 21st headliner.