Here are some facts on Glastonbury, the world's biggest open air arts and music festival which officially opens Wednesday. The main event starts Friday and ends Sunday night.
It covers 900 acres in the "mystical" Vale of Avalon, where legend claims King Arthur was buried, Joseph of Arimathea walked and where ley lines converge.
The festival is notorious for its torrential rain after three 'washout' years in 1997, 1998 and 2005 in which the entire festival site on Michael Eavis's Worthy Farm, deep in southwest England, became a slippery quagmire. Some fans revel in the mud.
In previous years performers have included such famous names as Paul McCartney, Rod Stewart, David Bowie, Tom Jones and Robbie Williams and the veteran group Status Quo.
The first festival was held in September 1970 over a two day period with acts including Marc Bolan, Keith Christmas, Stackridge and Al Stewart. Around 1,600 attended with admission being just one pound - and that included free milk from the farm.
In 1971 the festival moved to the time of the Summer Solstice and was known as the "Glastonbury Fayre." It was paid for by supporters of the ideal so the entrance was free and took on a medieval tradition of music, dance, poetry, theater, lights and spontaneous entertainment.
The first "pyramid" stage was constructed out of scaffolding and metal covered with plastic sheeting, built on ancient Glastonbury-Stonehenge ley line. Acts included Hawkwind, Traffic, Melanie, David Bowie, Joan Baez and Fairport Convention watched by an estimated 12,000 people.
In 1981 the name was changed to the Glastonbury Festival and the decision was taken to build a new permanent Pyramid stage which doubled as a cowshed and animal feed store during the winter months.
Early festivals were closely linked to the Campaign for Nuclear Disarmament, and during the 1980s organizers had to seek licenses following the introduction of a local government act to regulate such events.
In 1985 the size of the site was increased by 100 acres as neighboring Cockmill farm land was purchased and the steadily increasing attendance figure saw 40,000 revelers.
1990 saw clashes between security teams and travelers which resulted in 235 arrests and became known as the Battle of Yeoman's Bridge. 1992 saw 250,000 pounds ($498,100) of donations to Greenpeace and Oxfam as organizers shifted the emphasis away from nuclear disarmament with the end of the Cold War. The 1998 festival broke the 100,000 attendance mark despite a second year of quagmire conditions.
Last year's festival, one of the hottest Glastonbury festivals in memory, provided plenty of hits and a few misses for 150,000 revelers, who put a brave face on the England team's defeat in the soccer world cup during the four-day event.
Their abiding memory may be Stevie Wonder's closing set, showing off his musical prowess throughout and even singing "Happy Birthday" to festival founder Michael Eavis on stage to mark the event's 40th anniversary.
Other 2010 highlights included English rock band Muse, who were joined by U2 guitarist Edge for a rendition of the Irish group's famous hit "Where the Streets Have No Name." And there was a brief but popular appearance by Australia's Kylie Minogue, who joined Scissor Sisters to huge applause.
Irish rockers U2 will perform at the 2011 festival, joining Britain's Coldplay and U.S. singer Beyonce as the main headline acts. Veterans B.B King, Paul Simon and Don McLean are also featured in the lineup.