festival De Dannan, Galway, Ireland

Colin Harper witnesses some divine intervention at De Dannan's 21st birthday bash

If Alan Yentob threw caution to the wind and commissioned an edition of the Rock Family Trees show on the subject of Irish traditional music in the modern era, it would all start with Sweeney's Men in the late Sixties, begetting Planxty in the early Seventies and opening the doors for the Bothy Band, Clannad and De Dannan shortly thereafter.

Clannad's ethereal strand of the spectrum had happily stumbled into rock 'n' roll marketing by the middle of the Eighties - around the same time that De Dannan had started losing the plot. All the other greats split up at their peak, spawning a perpetuity of semi-legendary solo artists (Christy Moore, Paul Brady and all the rest). The trouble with De Dannan - named after the tuatha de danaan, a tribe of, ahem, god-like beings in Irish mythology - is that they've increasingly been perceived to exist in the same way that The Who exists: nothing for ages, solo projects that nobody's terribly interested in and, bang, before you can say "bandwagon", it's some kind of anniversary.

Two months ago, De Dannan fiddler and flag-bearer Frankie Gavin played to literally 25 people in a Galway solo show; this week his band's 21st anniversary bash could have sold out the Galway Festival's 1,200-seater marquee thrice over. It was a situation akin to Fairport Convention's annual reunion in Oxfordshire - a current line-up, whatever its own qualities (and young vocalist Tommy Fleming is a real find) that is effectively doomed to the looming shadow of its former members' subsequent reputations and left with only the name and the casual, rose-tinted goodwill of an ageing fan-base.

Old members trooped on and off the star-filled stage in suitably bemused incongruity - bodhran king Johnny "Ringo" McDonagh; Charlie Piggott, with crippled fingers but stroking a banjo for old times' sake; singers Mary Black and Dolores Keane; accordion wizard Mairtin O'Connor and so on. For all the soundness of the current line-up instrumentally, it took the truly phenomenal interplay of O'Connor and Gavin to really shift proceedings into fourth gear on "Jewish Reels", "The Arrival of the Queen of Sheba in Galway" and "Hey Jude" - three sets of idiosyncratic, teasingly fusionistic brilliance immediately resonant and indicative as to why this group is or was held in such regard.

Mary Black, singing "Annachie Gordon" for the first time in years, sang with a passion simply absent from her contemporary material; Dolores Keane was on cloud nine throughout; even grim-faced guitarist Alec Finn - Gavin's side-man all these years - looked by the end like he really missed the old days. They were all great musicians making great music once again. There were seven encores - more were deserved. The glory days are over, but if they have a resurrection like this every year, the old gods will always have believers.

Info from Galway tourist office (00353 9163081) to Sun