Metallica and Iron Maiden have been confirmed as headliners of the touring Sonisphere festival at Knebworth Park on July 4 through 6 next summer. Metallica’s show is billed as Metallica “by request,” which means that the fans who buy tickets to the show get to vote on what songs they want to hear.

Metallica drummer Lars Ulrich spoke excitedly about the festival in a statement: “This just works on all fronts. Metallica and Knebworth, Metallica by Request, Metallica and Iron Maiden. We are soooo excited about the limitless possibilities of our friends picking what songs Metallica get to perform on this forthcoming evening from the nearly 140 songs we’ve recorded throughout our ride. Who knows what crazy challenges will be thrown our way? Maybe a song that has never been performed live before? Maybe a few deep cuts that haven’t been aired in ages? Maybe a couple of your toe-tapping favorites? An obscure cover? Whatever happens, it will be unique, it will be special, and it’s all up to you.”

For Iron Maiden, the show at Knebworth will be the conclusion to their Maiden England tour. Said Maiden bassist Steve Harris in a statement: “Firstly it’s an honor to celebrate 40 years of rock at Knebworth, especially when you look at the list of great British bands who have appeared there over this period. Secondly, it’s the last show of our Maiden England tour, so it’s fantastic to be able to close this on home turf and in front of a lot of friends. You can be sure we will pull out all the stops!”

For information on ticket sales, visit the official Sonisphere Knebworth website.