Two out of three main headliners have been booked for a major festival, according to an organiser.

Martha Lytton-Cobbald, managing director of Lytton Enterprises, which manages Knebworth House its and grounds, has confirmed the return of Sonisphere Festival to Knebworth in 2014 and says several acts have already been confirmed.

The event will also be a celebration of 40 years of Knebworth House’s role as a popular music venue.

She said: “It’s really exciting. We had an inkling that we might be able to pull it all together a few weeks ago but we’re so pleased to say this is officially happening now.

“For it to be able to return on such an important anniversary really adds to the scale of this event. I think we are going to have some really world-class artists next year.”

Visit www.sonispherefestivals.com for more information.