The UdderBelly has been in storage at a warehouse in Yorkshire since its first outing last summer at the Edinburgh Festival Fringe.

It took three lorries to transport the huge structure through the dales and the downs to the Old Steine, where it has been gradually taking shape over the past week.

Come rain, shine or hurricane, the UdderBelly will remain on the Old Steine throughout May, providing this year's Brighton Festival Fringe with an unusual focal point.

At the early stages of construction the 400-capacity venue looked like the sort of main stage you might see at Reading or Glastonbury, albeit with four sides covered up rather than three.

But then the inflation started - and up popped a bovine head.

The UdderBelly was created by Ed Bartlam and Charlie Wood, directors of theatre venue company Underbelly.

Underbelly has been running venues at the Edinburgh Fringe since 1990, when it established a popular theatre site in old bank vaults in Cowgate.

The location inspired the firm's logo - an upsidedown purple cow.

When Ed and Charlie were looking for ideas for an original venue, it occurred to them a cow-shaped tent could be a fun possibility.

Charlie said: "We spoke to various designers and found it was a feasible, if rather odd, request.

"At Edinburgh last year people had the same reaction as if they'd walked into Doctor Who's Tardis.

"They were amazed that this strange structure actually contained a real theatre space.

"It attracted the attention of ordinary people in Edinburgh, who maybe didn't usually go to the theatre, and drew them in to come and see something, which is what a festival should be about.

Surprise "We hope the UdderBelly adds an extra air of to the performance.

"Normally, you walk into a theatre, it looks like a theatre and you're not really surprised.

Ed said: "The UdderBelly is meant to stimulate a reaction.

"It's fun and much more exciting than a marquee pitched on a piece of grass.

"It's not about enhancing the performances, because they should stand on their own two legs, but it should make the experience of theatre-going more theatrical."

The pair are aware the UdderBelly will be compared with its much-loved predecessor, the Spiegeltent.

Charlie said: "They are obviously two very different venues.

"Spiegeltent is this amazingly beautiful Belgian travelling tent with a wooden dance floor, chandeliers, stained glass windows and draped velvet, whereas the UdderBelly is a giant purple cow made from vinyl.

"We know it's a tall order and we need to put on a good show. Our programmes are very different - the Spiegeltent's was much more music-orientated, for example."

The UdderBelly was a last-minute addition to Fringe. Ed and Charlie approached the organisers after hearing about the Spiegeltent's decision to pull out - and did not have much time to put the shows together.

They have still managed to compile an impressive programme, which has proved popular with audience members.

Ticket sales are reportedly the best they have been for the site.

Shows by comedians Stewart Lee and Jerry Sadowitz have sold out and some dates for Tina C and headline act the Caesar Twins have also gone.

Charlie said they would like to make a return visit next year, adding: "I'm majorly in love with Brighton, the festival and fringe.

"It's very chilled-out, fun and challenging. I'd say the festival is at the stage where Edinburgh was ten or 20 years ago and I think it's just going to grow and grow."

There will be shows at the UdderBelly twice a day, at 7pm and 9pm, plus an afternoon show at weekends.

There will be DJs and dancing every night at the Festival Club and an outside bar serving milkshakes and steak sandwiches from noon.

The programme features a mixture of genres - from the acrobatic feats of The Caesar Twins to the dark comedy magic of Jerry Sadowitz.

Music ranges from rockabilly to brass band.

There is also a political drama about the Iraq conflict, a musical about the holocaust and Darfur and biographical comedies about Kenneth Williams and Bill Hicks.