Cheryl Cole, Rihanna and JLS are among the artists confirmed for this year's Radio 1 Big Weekend held at Bangor's Faenol Park, Wales.
Florence and the Machine, Dizzee Rascal, Alicia Keys, Justin Bieber and Paramore will also take to the main stage on 22 and 23 May.
Fans can apply for free tickets via Radio 1's official website.
Now in its 10th year, last year's Big Weekend, held in Swindon, was headlined by Snow Patrol and The Prodigy.
Elsewhere, Faithless (Saturday) and Vampire Weekend (Sunday) will headline the In New Music We Trust stage.
Australian duo Pendulum will retrun to the event after playing in Maidstone, Kent in 2008.
Speaking to Newsbeat bass guitarist Gareth McGrillen said: “That particular show was almost like a milestone for us last time we did it. It was a big turning point for us as a band. To be asked back is a pleasure.”
The BBC Introducing Stage and Outdoor Stage will be announced later this week.
The full line-up so far: SATURDAY 22 May MAIN STAGE
Florence and the Machine
Dizzee Rascal
Alicia Keys
Lostprophets
Cheryl Cole
Chipmunk
30 Seconds To Mars
Justin Bieber
Scouting For Girls
INMWT STAGE
Faithless
MGMT
Ellie Goulding
Tinie Tempah
Bombay Bicycle Club
Hadouken
Stornaway
Example
SUNDAY 23 May MAIN STAGE
Rihanna
Pendulum
Biffy Clyro
Ke$ha
JLS
Paramore
Jason Derulo
Pixie Lott
Paolo Nutini
INMWT Stage
Vampire Weekend
You Me At Six
Sub Focus
Plan B
Marina and the Diamonds
Kids In Glass Houses
Delphic