In 1973, Led Zeppelin kicked off their North American tour, which at the time became the biggest and most profitable rock and roll tour in US history. During the trek they traveled in a Boeing 720 jet that boasted a bar, a shower, a 30-foot lounge and a white fur bedroom. The jaunt grossed over $4-million. In 1970, the National Guard killed four students and wounded eleven more during an anti-Vietnam War protest at Ohio’s Kent State University. Soon after, Neil Young went into the studio with the rest of In 1974, Grand Funk Railroad started a two-week run at number one on the charts with their cover of