By Tom Bishop
BBC News Online entertainment staff
The Glastonbury Festival has grown and thrived since it began in 1970 but has this been at the expense of its free-spirited approach?
Glastonbury became known for its diverse mix of revellers
In April 112,000 tickets to this year's Glastonbury Festival were snapped up within 24 hours at the cost of £112 each. Thousands were left disappointed by booking problems and stricter ticket allocation.
Go back 20 years and the 1984 Glastonbury CND Festival featured Billy Bragg, Fairport Convention and The Smiths performing to 35,000 people. They either paid £13 each for tickets, or climbed in over the fence when no-one was looking.
It was also the year that the Green Fields, an area dedicated to environmentally-friendly stalls and workshops, were created.
"There was a belief that everybody has a place, a value and a worth," said its co-ordinator Liz Eliot.
Since then the festival has undergone dramatic changes. Founder Michael Eavis met increasing demand by renting land from neighbouring farms to progressively expand the festival.
This created space for more diverse acts, such as jazz, cabaret and circus performers, innovations such as the surreal Lost Vagueness field and live television broadcasts.
But Glastonbury's increased popularity brought new problems. The festival soon reached its full capacity yet for many years non-paying visitors were tolerated.
This led to overcrowding and tension, and no Glastonbury festivals took place in 1988, 1991, 1996 or 2001 as organisers recovered from confrontations between revellers and police, and the destruction of its perimeter fence.
The expanded festival incorporated a wider range of attractions
"In order for the festival to continue we have to keep the numbers within limits that can be shown to be safe," Eavis said in 2002, pledging no further expansion and unveiling a £1m security fence that symbolised the end of Glastonbury's easy-going attitude.
Sherie Haynes, 31, has been going to the Glastonbury Festival since she was 19, attracted by its "people and atmosphere" rather than the music.
"What struck me last year was how white and middle class the crowd had become," she said.
"The ticket price and debit card booking system has made it harder for some people to attend, such as travellers, so the crowd has become less diverse."
Nevertheless she admits increased security measures have been effective, with reported crimes dropping by 43% last year.
"If we want safety and less crime at Glastonbury we are going to lose a bit of its chaos," she said.
Since 1994 Scotland's T in the Park festival has expanded to accommodate 65,000 people per day. Geoff Ellis, chief executive of promoter DF Concerts, said: "It was obviously hard to change something like Glastonbury with years of history behind it.
"But unlike T in the Park, Glastonbury pre-dated licensing laws which now require stricter safety conditions and ticketing rules. It had no choice but to change."
Mr Ellis added: "Festivals also need to adapt to the changing needs of their visitors. We get feedback every year about our music, our toilets, our fairground rides. You can never rest on your laurels."
Festival fan Karen Algacs, 32, admitted climbing over the old fence to enter free on two of her seven Glastonbury visits.
"I understand why they had to tighten up security, but the festival has lost that element of freedom, and some of its edge, as a result," she said.
Nevertheless this year she will once again join friends camping near the festival's Green Field. "At first I came for the live music, but now it's as much about the people I see here every year."
Glastonbury now attracts a mix of committed devotees and newcomers keen to sample the modern festival experience.
Glastonbury gatecrashers led to problems with overcrowding
The prospect of more regulated conditions did not deter a reported 20-fold increase in the number of Glastonbury ticket applicants this year.
While modern festival requirements may have clashed with Glastonbury's original easy-going attitude, its ability to adapt has ensured its survival.
Tony Scott, director of Surrey festival Guilfest, sees a healthy future for music festivals as a result.
"Festivals may have been 'free and easy' in the past, but they had a bad reputation among the general public," he said. "Today they are a much less daunting prospect."
"At Guilfest and the Isle of Wight you can see these festival goers who are in their forties who went to festivals 15 or 20 years ago.
"They have taken a break, had families and now want a bit of the action again. So older music fans are mixing with young people - that has to be a good thing."