Lady Rotherwick gets ready to rock the manor at Wilderness Festival

Lady Rotherwick sits on a grassy slope overlooking a clear blue lake, and gently smiles.

The valley is silent, save for birdsong and the rustle of leaves, and the landscape empty apart from the occasional deer.

The peace will not last for long though. From today until Sunday, 30,000 people will descend on the grounds of Lord and Lady Rotherwick’s 17th century Cornbury Park, for the country’s most eclectic, and unusual, summer festival – Wilderness.

Anyone else might have second thoughts about allowing thousands of revellers onto their land. But not Tania, as Lady R is more familiarly known.

“We are really excited,” she says. “It’s a lovely festival and is our favourite weekend of the year, without a doubt. And it all looks unbelievable.”

Slim and glamorous, today sporting tight white jeans, a trendy blue T shirt, chunky bangle and deck shoes, Tania looks more like one of Wilderness’s hip festival-goers than a country landowner. But then that may be why she has been so willing to throw open the gates of her estate to Wilderness, and, for seven years before that, to Cornbury Festival.

“I love the lead-up to Wilderness and the festival itself,” she says. “It’s wonderful to see so many happy people. Imagine 30,000 chilled, unstressed people all having a good, wholesome time.”

Over the past five years, Wilderness has established itself as the hippest of festivals, attracting the likes of Spiritualized, WilcoRodriguez and London Grammar. This year music comes from Bjork, singer-songwriter Ben Howard, jazz-funk artist George Clinton, Moloko’s Roisin Murphy, Nick Mulvey and Nils Frahm among artists covering everything from folk and country to classical, electro-house, burlesque and blues.

But it is not the music which brings people to Cornbury; it is everything else. Its programme encompasses theatre, debates, comedy, forest craft and country pursuits.

There is also a lakeside spa, swimming in the lakes and food. Not just any festival food either; at Wilderness banquets are cooked by Michelin-starred chefs – this year including Angela Hartnett, Nuno Mendes, James Knappett, and Raymond Blanc.

“This year’s Wilderness has a really good line-up,” says Tania. “I love every year, but I think this is the best so far – and Bjork will make it really special.”

And what else is she looking forward to? “Ben Howard will be fabulous but also Nick Mulvey, whose music I love, and Nils Frahm. My 14-year-old, Gus, has been my DJ and playing songs from all the acts coming this year, so we have got to know their music.”

She advised festival-goers not to miss Saturday night’s showpiece spectacle – a high-wire acrobatic display followed by a procession featuring elaborate puppets.

“It’s the sheer diversity of what’s going on that makes it so amazing,” she says.

“My hot tip is to get a festival programme as soon as you get here, just so you can highlight those things you want to see. There’s nothing more annoying than getting to the end of the event and seeing how much you’ve missed.”

• The Lady and the camp: Lady Rotherwick and the 17th century Cornbury Park, at the heart of the festival site

She said the whole family got involved, with friends and relatives staying in the house or in spacious tents on the lawn. Guests include her mother. “She always rocks on down,” she laughs. “She’s a firm supporter, along with a lot of other older people.”

One regular who won’t be joining Tania this year, however, is her sister Diana, whose husband Mark Carney is Governor of the Bank of England. “She’ll miss it for the first time ever, because she’ll be in Canada with the children, but Mark might still drop by.”

Festival-goers can also expect a sprinkling of supermodels and members of the local Chipping Norton set. “There may be some well-known faces,” she laughs, but remains too discreet to name names.

She said the landscape of Cornbury Park, with its lakes and ancient forest, made the event what it was. “A lot is to do with the setting, but it’s also the creative geniuses behind it. They really care about the environment. It’s not the kind of festival that could be plonked anywhere .

“My children love it more than anything in the world. Gus will be here with his friends and is beyond excited, as is my eight-year-old, Clemmie.

"It’s such a safe festival, but the thing I love most about Wilderness is that there’s a freshness to it.

“There’s a surprise around every corner.”

Where & When
Wilderness Festival. Cornbury Park, Charlbury from today to Sunday
For details and tickets go to wildernessfestival.com