IF you happen to see an orchestra performing on Leytonstone’s Green Man Roundabout on Saturday, July 11, fear not, you have not had too much sun, it is in fact a rare full-scale performance of Cornelius Cardew’s The Great Learning.

The English avant-garde composer was a Leytonstone resident until he was tragically killed in a hit-and-run accident in 1981, and this unique opportunity to hear his six-and-a-half hour epic forms part of this year’s Leytonstone Festival.

Speaking about the marathon piece, organiser James Bull tells me: “The Great Learning is not traditional, it is very improvised. The whole point of the piece is to be music performed by people who don’t have musical training.

“Our performance will be a semi-performance, semi-workshop and split across five venues, starting at St Andrew's Church, moving to the Green Man Roundabout, then The Quaker Meeting House, St John's Church and finally the old Woolworths. Anyone who turns up can take part in most of the sections.”

Divided into seven so-called ‘paragraphs’, Cornelius, who began composing the piece in 1969 and founded the experimental music ensemble the Scratch Orchestra, incorporated a number of unconventional sound-sources in the score, from using stones and whistles in the first section, to banging cushions with sticks in the fourth.

While Cornelius created the piece to encourage untrained musicians to make their own music in a concerted attempt to break with elitist values of the music world, James admits he doesn’t quite fit the mould.

“Really rather badly for this work I’m a musical graduate from Goldsmiths," the 23-year-old confesses. “But as long as you have an understanding of what he was trying to achieve then it works well. I actually performed bits of The Great Learning two years ago at a memorial concert for what would have been his 70th birthday.”

Cornelius Cardew will also be remembered with a night dedicated to his work at O’Neills on Monday, July 13, which will see the great clarinet player Theo Jorgensmann make his first UK appearance.

Other festval events include a Night of South African Jazz at Stratford Circus (Sunday, July 5), the London Swingfonia at Kirkdales Wine Bar (Saturday, July 4), The Diary of Anne Frank presented by the Woodhouse Players at the Welsh Church Hall (Friday, July 10), and a performance from legendary guitarist John Etheridge at the Luna Lounge (Sunday, July 12).

The Leytonstone Festival launches with an opening ceremony complete with marching band on Saturday, July 4. The festival then runs until Sunday, July 19.

Details: 020 8555 6623 www.leytonstonefestival.org.uk