Metallica plan to hit the road next summer, playing a bunch of dates throughout Europe. And they're letting their fans pick the set lists. Best of all, they're leaving one slot open for a brand new song they plan to play every night.

While only three cities have been announced for the band's Metallica by Request tour -- all in Germany, all during the first nine days of June -- the group is promising more dates as well as exclusive set lists. After fans purchase tickets online, they'll be sent an e-mail with a code that will allow them to choose which songs they want to hear at the show.

As a press release issued by the band states, they'll be performing 18 songs every night, leaving "17 slots for you to choose ... so vote for all your favorites from the close to 140 songs we've recorded in our career." That extra spot goes to a brand new song that Metallica will premiere during the tour.

"We are once again psyched to break free of the four walls in the studio to get energized by our devoted European friends for a couple of weeks next May and June," said Lars Ulrich. "On top of that, the fact that all our nutty fans will pick the songs we play should be some next level fun and take a big load off my shoulders as the guy who usually writes the set list."

Once tickets go on sale -- the first batch will be available tomorrow -- Metallica will post the results of fans' voting on their website, so nobody should be too surprised by what they're hearing at the shows. They can also probably expect to hear a few deep fan favorites as well as the usual 'Master of Puppets' and 'Enter Sandman' that have been part of their set lists for decades.