50 years ago, December 6, 1969, more than 300,000 people gathered at the Altamont Speedway for an all-day festival billed as ”The West Coast Woodstock”. They left their cars on the side of the road, and filled the brown hills around Alameda County, California, to drop acid, smoke dope and listen to Rolling Stones, Grateful Dead, Jefferson Airplane, Santana and Crosby, Stills, Nash & Young. It was supposed to be an extension of the “peace and music” mantra marketed by Woodstock four months earlier, but the trouble began early and would not abate.

The festival almost didn’t happen. It was not ready on December 6. Just hours before, the massive event had no home. Golden Gate Park was dropped as the venue because of logistical concerns. An offer was made late on December 5 by the owner of Altamont Speedway. Within hours, the equipment, stage and crews were rushed to Altamont. There was a mad dash as the 300,000 music fans rushed to the speedway. A 30-mile traffic jam gridlocked the roads into the speedway.

On the way in, a young man fell in an irrigation ditch and drowned. His death was the first of four that day.

Grace Slick, singer for Jefferson Airplane:

“The vibes were bad. Something was very peculiar, not particularly bad, just real peculiar. It was that kind of hazy, abrasive and unsure day.”

Because it was all last-minute, Altamont Speedway was not ready to host hundreds of thousands of fans. All they had to separate the crowds from the stage was one thin rope. It disappeared, and fans moved up to touch, talk to and sometimes assault the performers.

In 2014, Slick told Rolling Stone that hiring the Hells Angels as security for the concert was partially her idea. Slick

“We were talking to Mick Jagger about how we’d done a bunch of stuff free in Golden Gate Park and the Hells Angels had been our security. And they never hurt anybody. And they were good at it because people were afraid of them. So we said, ‘We’ll get the Hells Angels to do security’, and Jagger said OK. But it turned out to not be right. There was speed and alcohol and those two things are God-awful.”

San Francisco Hells Angels member Gordon Grow:

“They said, ‘All you gotta do is just keep people off the stage. We said, ‘Yeah, no problem. We can do that.’ They asked us, ‘What do you want for that?’ We said, ‘We’re not cops. We’re not security guards. Just give us some beer.’ They said, ‘OK.”

22-year-old Carlos Santana stopped his set during the first song because a fight erupted near the stage. By the time Jefferson Airplane took the stage, the crowd and the Hells Angels were drunk and raucous. Marty Balin, singer for Jefferson Airplane knocked unconscious by a member of the Hells Angels. The Grateful Dead, who planned to play their set later in the afternoon decided to leave. The Rolling Stones landed in a helicopter and were immediately surrounded by fans, one of whom walked up to Jagger and punched him in the face, all caught on camera for the documentary Gimme Shelter directed by Albert and David Maysles and Charlotte Zwerin.

There were no bathrooms and no food.

It took more than an hour for the Rolling Stones to take the stage. The crowd turned surly and tension was high. From the moment the band started their set, it was chaos. Gimme Shelter shows the scene: Jagger trying to sing and Hells Angels and fans fighting. Jagger begged the crowd to calm down. In the film, Keith Richards can be heard saying.

“Either these cats cool it, man, or we don’t play.”

A guy took off his clothes and tried to climb up onstage, and the Hells Angels jumped off the stage and stomped people, beating them up with pool cues.

A man in the crowd held up a pistol and a Hells Angel rushed him with a hunting knife. Jefferson Airplane was leaving Altamont in a helicopter as it happened. An 18-year-old black kid, Meredith Hunter, was stabbed by Alan Passaro. The Rolling Stones didn’t know anyone had been killed, and kept playing, a moment immortalized by Don McLean in his song American Pie:

”And as I watched him on the stage, my hands were clenched in fists of rage.

No angel born in heaven could break that Satan’s spell.

And as the flames climbed high into the night to light the sacrificial rite, I saw Satan laughing with delight the day the music died.”

The Rolling Stones finished their set. Jagger later said they were afraid if they stopped, a full-scale riot would break out.

As the crowd slowly dispersed, two men were killed when a car ran them over as they huddled around their campfire.

Local farmers suffered tens of thousands of dollars in damage. Fences had been torn down and fields were trampled beyond use.

The next year, Passaro was tried for Hunter’s murder. Footage from Gimme Shelter was shown at the trial. Jurors acquitted Passaro deciding he acted in self-defense.

1969, the year of Woodstock, ended with Altamont. What happened at Altamont made the front page, but it has become a footnote. The 1960s, the decade that also brought us Vietnam, race riots and the assassinations of our best leaders, ended with disastrous exclamation point. Four people were dead. The next day, Jagger told the press:

“If Jesus had been there, he would have been crucified.”