Twenty years after the release of 'Superunknown,' Soundgarden plan to play the album live from front to back for the first time ever. They'll do it at the iTunes Festival during South By Southwest in Austin, Texas, on March 13. The show will be streamed live via iTunes.

Soundgarden's lineup for that concert will include drummer Matt Cameron. He is sitting out all other 2014 Soundgarden shows due to his obligations with Pearl Jam and the desire to spend more time with his family.

'Superunknown' is Soundgarden's most commercially successful album, peaking at No. 1 on the Billboard 200 album chart and selling more than 5 million copies in the U.S.  It also spawned radio hits such as 'Black Hole Sun,' 'Spoonman' and 'Fell on Black Days.'

Special 20th anniversary editions of 'Superunknown' will be released June 3. The two-disc deluxe edition features the original remastered album along with a collection of demos, rehearsals, b-sides and more.

The massive super deluxe edition includes the two deluxe edition discs, plus two other discs with additional demos, rehearsals and b-sides. A fifth disc has the album mixes in Blu-Ray Audio 5.1 Surround Sound. Other goodies include a hardbound book with a lenticular cover, liner notes by David Fricke and newly re-imagined album art from Josh Graham.

Soundgarden also have a vinyl release coming out on the annual Record Store Day April 19. The ‘Superunknown’ singles and associated b-sides with new artwork sleeves by Josh Graham will be reissued as five limited edition 10-inch vinyl records.

In addition to the iTunes Festival show, Soundgarden also have concerts scheduled all across the globe this spring and summer. They'll be playing in South America and Europe before returning to the U.S. for a July 4 show in George, Washington. For all their dates, go here.