Cass Elliot died in London during the tour on July 29 . Nash relayed the news to Kunkel , who was married to her sister Leah . Kunkel said , " She had a big role in their lives . She introduced Graham to Stephen . It was a very difficult day for us when she died . Thank God we were in the middle of doing something we could n’t stop . The show that night is probably what got us all through it . " Although large multiple-bill festivals such as Miami Pop , Woodstock , and Watkins Glen had taken place , and CSNY , the Rolling Stones , and others had played infrequent stadium shows , no band except for the Beatles had ever attempted a tour of this magnitude . Whereas the Beatles had done a series of stadium dates over two weeks in 1966 , the scope of this tour and its logistics were unprecedented ; the tour visited indoor sports arenas , race tracks , and smaller college stadia , including Chicago Stadium , Nassau Coliseum , Boston Garden , the Capital Centre , Jeppesen Stadium at the University of Houston , and the St. Paul Civic Center
Miami Pop
Miami Pop Festival (December 1968)
CSNY 1974