Later this year, Sigur Rós’ breakthrough sophomore album Ágætis byrjun is turning 20. To mark the occasion, it is getting an expansive 20th anniversary edition that’ll be released on 6/21, just a week after the big day.

The fullest version of the box set will include seven vinyl and an 84-page cloth-bound book. Those seven vinyl will include 3 discs worth of rarities and demos, some of which have never been released before, and 2 discs of a live recording of a concert that the band played at the Icelandic Opera House in June 1999 for the album’s release. (It was the last show that the band’s original drummer Águst Gunnarsson was with the group.) The book features photos of the band and ephemera from around the studio, including handwritten string arrangements and early business cards.

The 20th anniversary edition will also be available as a 4x CD and and 2x LP. More information on all of that and pre-orders can be found here.

Right now, you can hear the band performing “Flugufrelsarinn” from the Icelandic Opera House show below.

The Ágætis byrjun 20th anniversary edition is out 6/21.