From June 16 to 18, 1967, an "international pop festival" was held in Monterey, California. The three-day event was attended by 200,000 people, admission was $1, and the gate receipts went to charity. A mix of artists performed for free; Ravi Shankar, who played all afternoon, was the exception. Janis Joplin, then unknown, emerged as one of the stars and Jimi Hendrix stunned the crowd by setting his guitar on fire. They would both live only another 3 years.
The Monterey International Pop Festival is regarded as the first major music festival (Woodstock would come two years later) and marked the beginning of the Summer of Love in the San Francisco, the rise of Haight-Ashbury, and helped establish hippies as a counterculture group.
It's not the original, but the Mudd has the Kronos Quartet doing a little Purple Haze.