Florida Georgia Line are set to launch their inaugural outdoor FGL Fest on Sept. 8, and the debut lineup is stacked. While the country duo will headline the festival, they'll be bringing many of their friends and former tourmates — like Cole Swindell and Nelly — to round out the performances.

Additional acts set to take the stage at the Indianapolis Motor Speedway: RaeLynn, Jillian Jacqueline, Mason Ramsey, Riley Green and Stephanie Quayle. The festival will coincide with the Big Machine 400 at the Brickyard Powered by Florida Georgia Line race, which takes place at IMS on Sept. 9.

Tickets to FGL Fest will go on sale on July 6 at 10AM ET via Ticketmaster.com, LiveNation.com and IMS.com.

Florida Georgia Line continue to push boundaries with their music. Their recent single "Meant to Be" with Bebe Rexha has become a crossover hit at both country and pop radio. The duo dropped their latest single, "Simple," in June, and with it took a turn back to banjo-pickin' country. "Simple" leads the duo's forthcoming studio album, expected for release in early 2019.

"With this feel-good tune, we’re going back to basics…the stripped-down roots," says Brian Kelley. "We’re so excited that fans are vibing with its simple nature."

Ahead of their own festival, FGL will headline the 2018 WE Fest in August.

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