The Woodstock myth is a potent and evocative symbol of the '60s utopian hippie dream – the ultimate example of the unifying power of music, peace and love. To mark the 50th anniversary of one of the festival, this programme explores the impact of the now legendary celebration and why the spirit of Woodstock still carries important social lessons, providing evidence that the power of ordinary people can effect change. Musicians, artistes and organisers who were there, including John Sebastian, Roger Daltrey, Carlos Santana, Michael Lang, Michael Wadleigh, Arlo Guthrie, David Crosby, Richie Havens, Eddie Kramer and Stephen Stills, explain how the pinnacle of the optimism that they all shared as a generation included 500,000 young people enjoying three days of what was billed as "an Aquarian Exposition". Presenter: Arlo Guthrie