By the time the sun rose on the other side of the nation, San Francisco had become the epicentre of a spiritual earthquake, a new consciousness driven by LSD and mescaline. Come the summer of 1969, every small town in the United

States was touched by the revolution as half a million long-haired young people swarmed to a farm in New York State for the “Aquarian celebration of peace and music” that was Woodstock.

Inevitably, the cold winds of winter soon arrived and brought with them the after-shock. December 1969 marked the end not only of the decade, but of gentle optimism. Drug dealers had taken over the free-love hippie capital of Haight-Ashbury in San Francisco, and of the 300,000 people who made the trip to the “west coast Woodstock” at Altamont Speedway in north California, too many were carrying guns, clubs and knives. Fuelled by alcohol and methamphetamine, the festival erupted in violence and, finally, a fatal stabbing.

Woodstock started so innocently. John Roberts was 24 years old and itching to spend some serious cash. A recent graduate of the University of Pennsylvania, he was a wealthy entrepreneur who knew little about rock ’n’ roll,

so he felt perfectly qualified to organise what became the maddest, muddiest, messiest and most loss-making festival in music history. Nowadays, rock festivals are super-efficient corporate events, run with military discipline by accountants and lawyers. Even so, many still lose money. It is typical of the heady

optimism of 1969 that Roberts and three friends, Joel Rosenman, Artie Kornfeld and Michael Lang, believed Woodstock could be anything but a shambles. When the beans were counted, they had lost more than $2 million. And yet it is still widely regarded as the best rock festival ever.

The famous red handbill circulating the bars and coffee shops of Greenwich Village that sweltering summer makes even Glastonbury look like a pub gig. Almost any of the acts mentioned on it could headline a modern festival: The Band, Blood Sweat and Tears, Paul Butterfield Blues Band, Canned Heat, Joe Cocker, Creedence Clearwater Revival, Crosby, Stills and Nash, the Grateful Dead, Jimi Hendrix, Janis Joplin, Santana, Sly and the Family Stone, The Who and Neil Young. As the 40th anniversary of Woodstock on August 15 approaches, some of these artists are still pulling big crowds on the global gig circuit.

The sole representatives from Scotland were the Incredible String Band, who had formed in Edinburgh in 1965. In the sixties, it was rare for a Scottish band to have any kind of impact on the UK national charts, far less tour the US. The only other Scottish band of any significance at the time were Marmalade, Glaswegians whose unmistakably pop tunes would have made even less of an impression on the stoned American hippies than Lulu, the other Scottish pop chart act at the time. Donovan might have been well received at Woodstock, although he was playing down his Maryhill roots. Then again, the sea of hippies at Max Yasgur’s 600-acre dairy farm south-west of the town of Woodstock in upstate New York may have seen him as a softly spoken Dylan imitator. So the String Band it was.

They were big by any standards. The first Scottish band to play a headline tour of the States, they were riding high on the worldwide success of two albums – The Incredible String Band (1966) and The 5000 Spirits or the Layers of the Onion (1967) – that many regard as the first “world” music, decades ahead of the likes of Peter Gabriel and Paul Simon. Those albums combined Scottish folk with eastern music and anything that could be banged, bowed, strummed or plucked. While most of the band’s contemporaries were scribbling catchy tunes that revolved around panting adolescent lust, the String Band’s founding members, Mike Heron and Robin Williamson, crafted thoughtful lyrics full of Blake-like poetry, philosophical musings and spiritual wanderings.

To a generation of highly educated intellectuals newly liberated by the spiritual insights of pure LSD and mescaline, chemically unadulterated hash and marijuana, the concepts of peace and racial and sexual equality were second nature. The String Band had become the musical expression of a new consciousness.

Even the choice of location for the Woodstock festival seemed organic. Only a couple of hours from New York, Woodstock, a peaceful hamlet of artists and musicians, had been quietly hosting arts and music fairs since 1906. Almost 200,000 tickets were sold for the festival but the organisers were quickly overwhelmed by the arrival of almost twice that number of people in the run-up to the first day, and announced that admission would from that point be free. Word quickly spread and an estimated one million people attempted to reach the festival, with about half that number succeeding. Roads as far as 50 miles from the site were soon completely blocked. Despite this vast invasion, though, there were no reports of violence. In the history of live music, there had never been anything like it.

Now 66, Mike Heron still plays gigs, and recalls Woodstock fondly. “In Europe I don’t think people appreciated the mood of Woodstock,” he says. “Americans are the most patriotic people on Earth, yet here they were, saying no to Vietnam, burning their draft cards. There was a tremendous feeling of optimism, that we were at the dawn of a new age.”

The String Band had played New York’s Carnegie Hall the night before their scheduled set on Friday, August 15, but driving the short distance to the festival in Sullivan County was impossible. “We were ferried there by a rattling old military helicopter,” says Heron. “As we flew over Woodstock, all you could see were miles and miles of people. The pilot thought it would be a good idea to tilt sideways so we would get a better view, which, in a helicopter with no sides, was terrifying. I’ve never been so scared. We were holding on for dear life – us and a very shaken Ravi Shankar, who was flying with us.

“We were due to play Woodstock on the Friday night, alongside other acoustic acts, including Richie Havens and Melanie. But by then our girlfriends, Rose and Likky, were playing electric instruments with us. It was pouring rain and the organisers were afraid we would be electrocuted, so they asked us to play without the girls. We felt that would be disloyal and refused. We were rescheduled to play on Saturday after Canned Heat. By that time, most of the crowd were so stoned they weren’t in the mood to listen to fey Scots minstrels. In hindsight, it might have been better if Robin and I had played alone the previous night.”

The manager of the String Band, Joe Boyd, now aged 66, was a hippie Harvard graduate and colourful visionary who had worked with Muddy Waters and Bob Dylan before discovering and producing Pink Floyd. After spotting The Incredible String Band three years earlier on a trip to a barely legal folk club in Sauchiehall Street, Glasgow, he signed the band to Elektra. Despite having enjoyed one of the most successful careers in the music industry, the String Band’s schedule change at Woodstock still haunts Boyd.

“Friday night had been exhilarating, a terrific atmosphere,” he recalls. “Mike and Robin should have played an acoustic set, and they might have recaptured that wonderful magic of their early years. We were vaguely aware of the cameras at the side of the stage but we couldn’t know the film of Woodstock would eventually reach cinemas all over the world. If they had been in the film, it would have been a tremendous boost for their career. On Saturday, people were stoned out their heads, jumping in the mud to the thunderous beat of Canned Heat. You could sense the violence of Altamont was coming. The quiet String Band was the last thing the crowd wanted to see. I’m generally immune to regret, but that Saturday, knowing we had blown it, was the worst day of my life.”

Heron’s then girlfriend and bandmate, Rose Simpson, has served as Mayoress of Aberystwyth Town Council. She more or less lives the hippie dream, studying languages and dividing her time between her tranquil cottage in Wales and a little house overlooking the Pyrenees. Simpson has mixed feelings about the biggest gig in her life. “We could have done better, “ she says. “It was a disaster, really. By the time we played on Saturday, the crowd wasn’t in the mood to hear contemplative songs. It is uncomfortable when you see you’re only getting through to one in a hundred.”

Simpson recalls that the Friday afternoon at Woodstock was “like a big party”. “We spent the afternoon eating strawberries and cream, talking and laughing, splashing in the creek,” she says. “It was lovely. But then the rain came, the atmosphere changed, the roads were blocked and we were trapped. We couldn’t get away to a hotel, the organisers threw tents at us. Before I met the String Band, I used to do a lot of winter climbing in Scotland, so I was used to discomfort. It was damp and miserable, like camping in the rain in Glencoe.”

A quick online search reveals a picture of Simpson from the time, wearing a floaty white diaphanous dress and nothing else. “There was a lot of nudity, but when I see the pictures of myself there’s a certain innocence about it,” she says. “It wasn’t a come-on, it wasn’t like many pop singers today – a lot of that is just porn. It was part of the thing at the time, that women could dress as we pleased. It wasn’t a sexual thing. We were saying we were free.”

Woodstock had a lifelong effect on Simpson, and left her feeling that nothing could ever rival the sensation. “It wasn’t our best performance, but it was still an amazing experience – the high of highs,” she recalls. “There is nothing like playing to a crowd that big. There is nothing else you can do in life that comes even close.”

Likky McKechnie, Robin Williamson’s Edinburgh-born girlfriend and String Band member, may be the only female rock star ever to play a gig with her front teeth missing, but somehow the black, childlike gap only added to her fragile beauty. A slight, pixie-like creature, she disappeared many years ago, amid tales that she had become homeless in Los Angeles, a sad encore for any Woodstock performer.

Then, of course, there was Williamson himself, a musician of stunning fluency, a gentle troubadour who still regularly plays with his wife Bina, “carrying on the spirit of Woodstock, and the original concept of the String Band”. Aged 65, he looks like Merlin now. He is joyfully plump with a deep, resonant laugh, and is fond of tales of Irish mythology. Woodstock, Williamson says, marked a cultural turning point. “It was an extraordinary event,” he recalls. “A complete surprise. We were told we would be playing at a small folk festival. We thought it would be just another gig, then we saw all those people from the air. We had the sense that we were at a crossroads in time.” The thought that they might have appeared in a big-budget movie never occurred to him. “We were just playing music with a strongly spiritual element,” he says, “celebrating being alive in a simple sort of way.”

Standing at the side of the stage, Williamson and Heron watched as Jimi Hendrix played The Star-Spangled Banner. “It was absolutely startling,” says Heron. “Watching him do that, it felt like the world was about to change, that nothing would be the same again.”

Despite modern cynicism about hippies, many of the ideas regarded in the late sixties as the pipe dreams of dope-smoking dropouts have slowly become the bedrock of this century’s moral code. As Simpson says, “We were strong on children’s rights and the rights of people. This was new at the time, but is part of daily culture now.”

Boyd recalls Woodstock as a focus for the changes that were happening. “Thousands of young Americans who had not lived anywhere near Haight-Ashbury or Greenwich Village suddenly became aware there was a new way of looking at things,” he says.

“Civil rights, gay rights and tolerance all came from hippies. Right-wing politicians

still turn purple with rage when we talk about the sixties, so we must have been doing something right.”

It may have started as the fantasy of a young, stoned and far-too-rich dreamer, a so-called trustafarian, but in many ways Woodstock became the turning point of the 20th century. This month marks 40 years since a new collective consciousness emerged from the mud of Max Yasgur’s farm.

Perhaps unsurprisingly, John Roberts chose not to promote another festival, and breathed a sigh of relief when royalties from the film, the triple live album released in 1970 and the Woodstock trademark of a dove perched on the neck of a guitar eventually covered his losses. He turned his attention to cards and became a championship bridge player. He died in 2001 at the age of 56. n

Graham Forbes played guitar with the Incredible String Band from 1973-1974. Woodstock Experience by Michael Lang is a limited-edition box set published by Genesis Publications, priced £395. Visit www.genesis-publications.com. Images from the book will be shown at Idea Generation Gallery, 11 Chance Street, London, from Wednesday until August 30. Visit www.ideageneration.co.uk.