Bringing together a variety of acts from across the rock 'n' roll spectrum in front of a crowd of more than 300,000, California Jam II featured scorching performances by some of the biggest names in '70s rock music. The concert, which took place on March 18, 1978, helped pave the way for all-day festivals to become the routine big-business events they are today.

Planning a sequel to the original California Jam that occurred at the Ontario Motor Speedway in 1974, organizers had the benefit of learning from some past festival disasters, especially the slipshod planning and resulted in violence, death and the failure to maximize profits.

California Jam II was a success. Fans enjoyed a day of music from such top acts as Ted NugentHeartSantana and Dave Mason. Former Fleetwood Mac guitarist Bob Welch was joined onstage by Stevie Nicks and Mick Fleetwood during his set, while Frank Marino and Mahogany Rush and Foreigner also rocked the crowd. A funk-rock act called Rubicon – featuring a young bassist and singer named Jack Blades, who'd go onto Night Ranger – rounded out the lineup.

Like its predecessor, the concert was staged at the Ontario Motor Speedway in Ontario, Calif. But unlike the first Cal Jam – at which featured act Deep Purple had to leave the premises in a helicopter to avoid furious promoters after guitarist Ritchie Blackmore attacked a television camera with his guitar – the second concert came off, mostly, without a hitch.

Even though media reports incorrectly reported three fatalities and a large number of arrests, Robert Hilburn of The Los Angeles Times reported that the event was mostly peaceful and well-organized. He also noted that promoters repeatedly admonished the crowd from the stage in order to control potential problems before they could arise.

The festival drew more than 300,000 fans, and also spawned a successful soundtrack album and television special. The event's precise organization – and the profits derived from doing the job correctly – would help to usher in a new business model in which festival rock concerts were enjoyable, safe and profitable.

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