This will be the first time that Sigur Ros, who will present their latest album entitled "Valtari", will be on stage in Slovenia.

The band is making a unique, otherworldly, mystic and ethereal music, which is characterised by "transitions from minimalistic and peaceful parts to epic, atmospheric and full arrangements", the organisers of the concert, Mars Music, said.

The Icelandic band described "Valtari", which was released in May, as an "avalanche in slow motion". "While this sounds pretty unromantic, the result is far from it. Some sort of alchemy appears when the four members of Sigur Ros gather in the same room," Mars Music noted.

Vocalist and guitar player MojcART, who will open the stage, will be accompanied by guitarist Martin Lunder and cajon player Anže Žurbi. Melodrom will perform in a changed and enlarged company without the usual pre-recorded elements.

Organisers of the Mars festival, which has featured concerts by big names like Skunk Anansie and Moby since its beginning in 2009, told the STA that they expect some 3,000 visitors. This year, the festival will run as part of the 2012 European Capital of Culture.