2015 saw performances from Anna Calvi, Bombay Bicycle Club, Neneh Cherry, Honeyblood, Kurt Vile, and many more, and was a fabulous addition to the festival calendar. The second instalment looks to build on that as it features one of only two 2016 UK shows from Sigur Rós.

About their headline slot, Sigur Rós say: “We are pleased to announce that we are playing Citadel next summer. In the spirit of adventure, all we can say right now is it’s going to be different. In addition to playing all the songs you know and love, there will be new unreleased songs, a new show and more… trust us on this one.”

As well as a full music schedule, Citadel will feature speeches, debates, lectures, arts, crafts, workshops, yoga, relaxation therapies, gourmet grub, and delicious drink. There's even a sports day.

Citadel will take over the capital's Victoria Park on Sunday 17 July.

Registration for pre-sale is open now. The pre-sale opens Thursdayat 9am.

General sale starts Tuesday 1 December at 9am.

For more information, head to the Citadel website.