The event takes place at July 1-4, at Gdynia's Babie Doly Military Airport in Poland
The Prodigy Disclosure, The Vaccines and Kaytranada have all been added to Open’er Festival bill.
Open’er will take place between July 1-4, at Gdynia’s Babie Doly Military Airport, Poland, with headline sets from Mumford & Sons and Kasabian. D’Angelo, A$AP Rocky, Father John Misty, Modest Mouse, Django Django, Faithless, Of Monsters And Men, Refused and Major Lazer will also play, as will St Vincent, Alt-J, Radiohead’s Jonny Greenwood, Hozier, Flume, Tom Odell, Swans, Eagles Of Death Metal, Jose Gonzalez and The Dumplings.
Tickets are available from the Open’er Festival website now, with a four-day ticket with camping costing €150 (£113).
In the past, Open’er festival has seen performances from Pearl Jam, Faith No More, Jack White, Blur and Arctic Monkeys, among others. Last summer, The Black Keys said Open’er had “10 times the energy” of Glastonbury after headlining the Polish event, a sentiment echoed by Alana Haim, who told the Open’er crowd: “We’ve been on tour for two years and this is the craziest crowd I’ve ever seen.”
Open’er will mark Modest Mouse’s first European concert since 2010.