Final answer:
The first large scale outdoor rock festival organized by John Phillips was called Woodstock, held in 1969 in Bethel, New York. It attracted nearly 400,000 people, becoming a historic event that symbolized cultural revolution and featured 32 music acts over three days.
Step-by-step explanation:
The world's first large scale outdoor Rock festival that you're referring to, organized by John Phillips of the Mamas the Papas, is the iconic event known as Woodstock. This festival took place in mid-August 1969 and was held in rural Bethel, New York, becoming a symbol of the cultural revolution of the 1960s. The event attracted a massive crowd of nearly 400,000 people, which was far beyond the anticipated 50,000 attendees. Woodstock provided the opportunity for youth to form a community celebrating freedom, rebellion, and individuality, and featured 32 acts performing over a rainy three-day event.
Attendees enjoyed the music while partaking in substances like marijuana, LSD, and alcohol, embodying the counterculture of the era. Despite the expectations of crowd control and admission fees, the sheer number of people led to the festival effectively becoming a free concert, as Glenn Weiser recalled. This gathering not only highlighted the popularity of rock music but also marked a defining moment of independence and cultural expression for a generation.