A huge number of high profile artists have pitched in to participate in the recording, which features the cream of Irish rock and folk music, as well as a number of international names. In addition to members of U2 and Kila among those who streamed into Windmill Lane to contribute over the two days of recording were Sinead O'Connor, Christy Moore, Andrea Corr, Shane McGowan, Bob Geldof, Damien Dempsey, Gavin Friday, Jerry Fish, Paul Brady, Paddy Casey, Mick Pyro (of Republic of Loose), Mundy, Chris de Burgh, Ronan Keating, Eleanor Shanley, Mary Black, Declan O'Rourke and Mary Coughlan, as well as The Dubliners and The Chieftains.

Frames singer Glen Hansard recorded his vocals on a telephone from the Czech Republic. The record was produced by John Reynolds, engineered by Alastair McMillan and the session was filmed by John Carney, the director of Once.

The song, entitled 'The Ballad of Ronnie Drew', is a collaboration, written by the Grateful Dead lyricist Robert Hunter, with Bono, the Edge and the former Golden Horde singer and songwriter Simon Carmody. A friend and collaborator of Bono's, Carmody is central to the story of how the projectcame together.

"Simon seemed to think that Robert Hunter was a big fan of Ronnie," Bono told Hot Press. "Simon suggested that we get Robert involved in writing the song."

Hunter's lyrics provided the launching pad and the song was completed and demoed by members of U2, with Bono singing and Edge playing a Trez, a Cuban instrument given to him as a Christmas present by his wife Morleigh, on the demo, to achieve the appropriate folk flavour

Ronnie Drew is currently battling with cancer, which was the inspiration for – and inevitably gives added urgency to – what is a history-making project. "When you're fighting cancer you mood is critical," Bono says "We want Ronnie to know how much he is respected and loved."

As the night turned into morning on the second day of recording, with most of the musicians departed, producer John Reynolds laid down a couple of mixes for the remainder of the gathering to listen to. Bono, Andrea Corr, Moya Brennan and Simon Carmody all suggested modifications and changes.

As it turns out. 'The Ballad of Ronnie Drew' is a fitting tribute to the performer who first became famous with The Dubliners, and was the singer on their 60s chart hit 'Seven Drunken Nights' among other classic recordings.

"It is an astonishing record," Hot Press editor Niall Stokes revealed. "The song is powerful and poetic, with a number of brilliantly crafted standout lines. But with Bono, Shane McGowan, Christy Moore and Damien Dempsey all taking verses, the performances are amazing. And Sinead, Andrea and Moya are wonderful on the chorus. It's a certain Number 1."

"It was a real privilege to be part of it," Moya Brennan said. "The atmosphere in the room was amazing."

Andrea Corr was equally enthusiastic. "I don't want to go home," she said. "It is such an amazingly beautiful song and such a wonderful idea. It is the kind of occasion that you'll remember all your life. It is lovely to have been part of it."

"Everyone has been brilliant," Simon Carmody said, "so generous and giving with their time and delighted to do it. It's been great fun."

For the full story, see the latest issue of Hot Press.