Thousands of Glastonbury festivalgoers have arrived at Somerset’s Worthy Farm today to be greeted by settled skies and, for the first time in years, mud-free grounds.

An estimated 20,000 to 30,000 people have pitched tents since festival founder Michael Eavis threw open the gates to his farm yesterday, with the remaining 100,000 revellers expected to arrive tonight and tomorrow.

Weather forecasters have predicted a windy weekend but, with only light showers, say the mud baths of recent years are unlikely.

Festivalgoers, enjoying today’s dry weather, were wandering the site in shorts and T-shirts this morning, anticipating tomorrow’s opening acts, which include Kings of Leon, The Gossip and Kate Nash. A Glastonbury spokesperson said revellers were in high spirits and described the excited noise as akin to a “vocal Mexican wave.”

But despite the forecast, the festival has yet to sell out. Two weeks ago, organisers took the unprecedented decision to make the £155 tickets available on the high street through music chain HMV, but 1,000 remain unsold.

It is the first year that the festival has failed to sell out. Last year all 137,500 tickets sold within a few hours, after fans were required to register their interest and then battle other festival enthusiasts for a ticket.

Critics attribute the slow sales to organisers’ decision to book American hip-hop star Jay-Z as the headline act, at what has traditionally been thought of as a rock festival. But Eavis blames the torrential rain that has marred the festival in recent years.

Yesterday, he admitted he nearly gave up running the festival after rain turned the 2007 event into a mud bath.

"Last year I thought 'I don't think I can go through this again'. But it's like having a baby - it's painful at the time but you get over it don't you?

In 2005, the festival was hit by storms and 300 tents were washed away.

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