On the weekend of June 20-22, 1969, a former harness-racing track turned fairgrounds in the north San Fernando Valley held what was, for that moment, plausibly the largest pop festival the United States had ever seen. The Newport '69 Pop Festival — the name a holdover from a smaller 1968 event near Newport Beach, and nothing at all to do with Rhode Island — drew somewhere between 150,000 and 200,000 people across three days to Devonshire Downs in Northridge, two full months before Woodstock would make the form famous and then redefine it.

The bill was enormous and genuinely of its instant. Friday belonged to the Jimi Hendrix Experience, headlining over Ike & Tina Turner, Joe Cocker, Spirit, Taj Mahal and Albert King. Saturday brought Creedence Clearwater Revival, Steppenwolf, Jethro Tull, Love, and Eric Burdon fronting his new band War. Sunday closed with the Byrds, the Rascals, Three Dog Night, Booker T. & the M.G.'s, Johnny Winter and Poco. (Marvin Gaye was advertised on the poster but never appeared — he missed his plane.) Admission was seven dollars at the gate (six in advance); the 24-year-old promoter Mark Robinson had reportedly paid Hendrix something on the order of $100,000, an unheard-of sum for a single rock booking.

Hendrix played twice, and the two sets could not have been less alike. His contracted Friday performance with the Experience was, by wide agreement, a low point — short, ragged, the headliner reportedly walking off irritated; Mitch Mitchell later suspected someone had spiked his drink. But on Sunday he came back unbilled and led a loose, two-hour jam with Buddy Miles, Eric Burdon and Tracy Nelson's Mother Earth, and the LA Times's Pete Johnson wrote that the crowd "may have heard the best performance of their lives." It was among the last appearances of the original Experience, which would play its final show in Denver nine days later.

The weekend also carried 1969's darker undertow. By Sunday afternoon, with thousands more outside than the fences could hold, the gate-crashing turned violent: bottles and rocks, police batons, some three hundred injured and dozens arrested. Robinson, who grossed three-quarters of a million dollars, claimed to have lost money on the chaos. No festival was ever staged at the Downs again. The land is now the North Campus of Cal State Northridge; the site was razed in 2001. What survives is the poster, the bootlegs of that Sunday jam, and the festival's odd standing as the West Coast's big, troubled rehearsal for the summer that followed.