Girls Aloud will headline the opening night of Faenol 2007

X-Factor winner Shayne Ward and R&B singer Jamelia will also perform on the opening night at this year's Faenol Festival, now in its seventh year.

Opera night will see Spanish baritone Carlos Alvarez and Welsh soprano Rebecca Evans singing, along with Terfel himself.

The festival, on the Faenol estate near Bangor in Gwynedd, opens on 24 August.

'Wonderful audience'

Girls Aloud have had more than a dozen top 10 hits, including No Good Advice, Sound of the Underground and I'll Stand By You, since emerging from the TV show Popstars: the Rivals five years ago.

The five's greatest hits CD went to the top of the album charts towards the end of 2006.

Last year, more than 35,000 people attended the four-day event, which was set up by Terfel in 2000.

The opera singer said: "At the close of each year's festival I wonder how on earth we're going to manage to equal this next year?

"But every year this festival develops, it attracts more amazing artists as the Festival's international reputation grows.

Jamelia and Shayne Ward also play the opening night

"I'm always delighted to welcome them to this very special and stunningly beautiful corner of Wales and to introduce them to the wonderful and growing Faenol audience."

The contemporary music line-up will open the festival on Friday evening, with the world of opera coming to the stage on Saturday.

On the Sunday, Michael Ball and Broadway star Ruthie Henshall will be singing favourites from musicals.

The festival will close, as always, with Welsh rock and pop night.

Artists confirmed so far for Tan y Ddraig - or Dragon's Fire - include Huw Chiswell, Y Sibrydion and Bryn F�n.

Festival chairman Roger Jones, said: "Every year we go from strength to strength, and the festival's reputation grows.

"We look forward to welcoming back our regular supporters and visitors from across the UK and overseas."