Well, now we know three of the 40. The reunited OutKast have pledged to play more than 40 music festivals this summer, and now Delware’s Firefly Music Festival follows Coachella and Governors Ball as the third of those festivals. The festival comes to Dover International Speedway 6/19-22, and OutKast will join perennial rock-fest bill-toppers Foo Fighters and Jack Johnson as headliners. The undercard includes a lot of crap like Imagine Dragons and the Lumineers, but it also has Arctic Monkeys, Tegan & Sara, Weezer, Chance The Rapper, Band Of Horses, Sky Ferreira, Blood Orange, Iron & Wine, Sleigh Bells, Phosphorescent, A-Trak, White Denim, Vic Mensa, Sam Smith, and many others. You’ll find all the details here.