The Woodstock Music & Art Fair hosted what was supposed to be a festival of “peace, love and music” 45 years ago. Three days turned into four, and the 100,000 fans that were expected to show up turned into 500,000. For one rainy weekend in 1969, the rural community of Bethel became the third largest city in New York state.

Woodstock supposedly defined a generation and showcased some of the greatest music of the ‘60s, or so we have been told over and over again. But did it really? The lasting legacy of Woodstock was that it became a crucible moment for a community of young people thrown into a mud bath for a weekend. It's not that the music didn't matter, but it wasn't the main reason why Woodstock made history, or even the primary memory for most of the festivalgoers. Woodstock brought hundreds of thousands of people to an inconvenient location using dozens of bands as a lure – that’s the same formula for countless summer mega-festivals today. But the sheer size of these events ensures that the music becomes a soundtrack – rather than a focal point for a weekend of peace, love and partying like an extra in a Nicki Minaj video.

Woodstock-like rock and dance music festivals now so thoroughly dominate the North American and European concert business in the summer that it's difficult to tell them apart. They are all, in a way, working off the template set by Woodstock. And as seasoned festivalgoers can attest, these gatherings often become as much about the fans interacting with one another as with the music. The rituals codified by Woodstock explain why.

Before Woodstock, there was the Monterey International Pop Festival in California in 1967. It was a weekend in which Otis Redding, Jimi Hendrix, The Who and Janis Joplin became icons overnight, in part because people could actually see and hear their performances in relative comfort. The performance arena held about 7,000 people, and though many more congregated on the grounds outside, the music was the primary draw.

At Woodstock, most of the festivalgoers never got close to the stage, and most barely heard or saw the performers. The chaotic atmosphere didn't help either. Marty Balin, singer in Jefferson Airplane, which played both Woodstock and Monterey, once told me, "Monterey was a lot more organised and a lot more about the music. Woodstock was about fun ... but we didn't get to go on till dawn the last day, and by then we'd gotten drunk and sobered up four times. It wasn't our greatest moment."

Singin’ in the rain

This was a cultural happening in which the music was drowned out not only by the rain, but the magnitude of the event itself. Promoters built fences and set up 1,000 portable toilets, which soon proved no match for the horde of fans descending on the farm field outside Woodstock. A sound system custom-made for the event, including 70-ft (21m) speaker towers, was also overwhelmed by sheer numbers. “We set it up for 150,000 to 200,000 people,” engineer Bill Hanley once said. “Of course, 500,000 showed up.”

Countless more never made it as the New York state highway system was clogged with would-be festival attendees. Only one large stage held the performers and no video screens were set up (those wouldn’t become standard features at festivals until decades later). So most of the performers looked the size of ants to the audience, if they could be seen at all. The weekend turned into a struggle for basic amenities – food, shelter, toilets – as rain turned the field into a muddy quagmire. Yet many who attended and documented the festival still romanticise it. In the tradition of great American road-trips, Woodstock was the ultimate destination experience for the Vietnam War babies who showed up, turned on and rolled in the mud together. Meanwhile, in the distant background, Hendrix, Sly Stone and Santana were burning themselves into the consciousness of a relatively lucky few who could get close enough to see and hear them.

Even Danny Goldberg, a long-time music-industry executive who covered Woodstock as a 20-year-old freelance writer, once told me he went to see the bands but came away more impressed by the vibe. “My biggest memory was getting there and the warmth, the good feeling of everybody … The music was less of a memory.” The pioneering critic Ellen Sander acknowledged that though the line-up was stellar, the performances were “the least significant events of what happened over the Woodstock weekend.”

Rite of passage

Similarly, today's festivals offer music as a way to lure fans to a faraway place, but for many fans the event is about the experience as much as the bands. In general, it's easier to see and hear the performers, but they rarely command everyone's attention. Part of the reason is that music festivals have become about more than just music; they're also about selling merchandise, promoting products and building tourism. Multi-day events such as Coachella in California and Austin City Limits (ACL) in Texas inject many millions of dollars into local economies, bringing in revenue for surrounding restaurants, bars and hotels.

Over-exposure also dilutes the music's impact. So many festivals clog the summer schedule that there's rarely anything particularly unique about the line-ups. Many major bands play multiple festivals in one summer: Arcade Fire, for example, headlined both Coachella and Glastonbury in the UK in recent months. OutKast not only played Coachella this year, but Lollapalooza in Chicago, Roskilde in Denmark and just about every festival in between.

Who's playing can often become beside the point. Festivals "are a rite of passage," says Charlie Jones, co-owner of C3 Presents, which promotes Lollapalooza and ACL – a rite of passage in which music is just one of the attractions, not the attraction. No wonder Lollapalooza and Glastonbury festivals have sold out in advance the last few years before any of the bands were even announced. It's the party that matters.

Greg Kot is the music critic at the Chicago Tribune. His work can be found here

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