First Night: Glastonbury Festival, Worthy Farm, Pilton, Somerset

Fortieth festival begins in spirit – a day before the big bands tune up

(GETTY IMAGES)

The weather omens which rule the fate of Glastonbury more than the choice of bands looked cautiously kind on Thursday. Some mud-soaked paths had to be waded like minor streams, and wellies were occasionally clutched in quicksand-style snares. But unrelenting sun through the afternoon made it hard for anyone to be miserable, as Worthy Farm looked near to its best.

It's the 40th anniversary of an event which has become an unrecognisably gargantuan cousin of 1971's hippie village fete-style affair. With this weekend's Pyramid Stage headliners – U2, Coldplay and Beyoncé – depressingly bland, the Spirit of '71 stage is due to bring old troupers such as Melanie and Nick Lowe back together. More interestingly, it will allow reflection on what Glastonbury means now. It's a nationally televised cultural perennial somewhere between Wimbledon and Woodstock. Huge rock stars line up for the cache of headlining. Yet Michael Eavis's guiding hand (now being replaced by daughter Emily's) means unshakable ideals still hold Glastonbury back from its corporate potential.

Glastonbury Thursdays are the result of its seemingly inexorable mission creep. They began as an attempt to provide entertainment for those arriving early to beat Friday's melee. With over 93,000 on site already, this year DJs and astrology workshops were laid on for sizeable Wednesday hordes. There seems no logical end to the festival's benignly imperial expansion.

There was little significant musical life on Thursday, with all the major stages standing empty till Friday. This respite instead allowed the festival to emphasise its campaigning and eccentric sides. In the Leftfield, quietly chanting Hare Krishna devotees provided my first live music. "Drop the Debt" was among the slogans emphasising the enduring oppositional nature of a festival which was once vigorously wedded to CND. At Speakers Forum, Burma and the Bomb were among the topics, at the only rock event with Tony Benn as a welcome regular. Arcadia and Strummerville (honouring the late Joe Strummer) are among the spots waiting deeper in the fields, inviting visions of a bucolic, mystical England in the shadow of Glastonbury Tor. Many will spend the weekend there, never hearing a note of U2.

As Thursday ended, DJs soundtracked drunks stumbling through deepening mud in the dark. Solomon Islanders Narasirato provided my first musical highlight, racing through the crowd like raiding warriors in skimpy traditional garb, and blowing giant Pan's pipes. These engaging showmen sang, mostly joyfully but finally in ritual mourning, of a threatened culture. Their fee will help their village, flooded by ecological forces a bit of mud can't begin to bring home. The equally little-known but thrilling Penny Black Remedy (a London-Croatian equivalent to the Pogues) offered wryly funny songs of urban romance and drinking, as Glastonbury began to wake. Mysteriously fallen UK garage star Ms Dynamite was due to incrementally increase the musical voltage, before Friday's full-on star power. Thursday is the calm before this storm, and a reminder that Glastonbury's real meaning often lies elsewhere.