The annual iHeartRadio Music Festival has announced the lineup for this year's event in Las Vegas, and once again, country stars are part of the eclectic cast. Keith Urban and Tim McGraw will head to Sin City on Sept. 20 and 21, where they will join a number of other artists for two days of non-stop music.

Urban joined Ryan Seacrest, Miley Cyrus and 'Good Morning America's' Sam Champion in announcing the star-studded lineup, which includes Elton John, Justin Timberlake, Katy Perry, Maroon 5 and Bruno Mars. In addition, the Band Perry will perform on Sept. 21 at the new iHeartRadio Music Festival Village, joining Avril Lavigne, the Wanted and Ne-Yo, among others.

Country music has always been well represented at the event. Carrie Underwood, Rascal Flatts, Brad Paisley, Jason Aldean, Miranda Lambert and Taylor Swift have each played at previous festivals.

The third annual iHeartRadio Music Festival will be held at the MGM Grand Arena. Tickets go on sale this Saturday (July 20). For more information, or to purchase tickets, click here.