Ryan Seacrest Ryan Seacrest

Ryan Seacrest will host a two-day music festival in Las Vegas, featuring Lady Gaga, Coldplay, Bruno Mars and The Black Eyed Peas among others.

The iHeartRadio Music Festival, put on by Clear Channel Radio, will take place at the MGM Grand. Scheduled for Sept. 23-24, it will also be streamed online via www.iheartradio.com and on all Clear Channel radio stations.

"This is a once in a generation gathering of artists and fans from all over the country for a true, must-see music event," Seacrest said in announcing the event Monday.

Watch the American Idol host announce the concert and the acts set to perform: