THE latest acts playing Sonisphere have been announced by festival organisers and look set to blow Knebworth House away.

Coming straight off the back of completing their sixth studio album The Mars Volta have confirmed their return to british shores and will grace fans with an exclusive performance at Sonisphere.

The Texan prog rockers will be bringing their unique blend of Latin-American infused psychadelia to headline the Saturn Stage.

Guitarist, Omar Rodr�guez-L�pez, said: “We’re stoked to come and play.

“Everything I’ve heard about the festival has been positive, I’m sure it’ll be great.

“Playing live for me is the best part of being in a band, I can’t wait to get back out there. I’m excited to play the new songs.”

Sweden’s mighty Opeth, will also debut at Sonisphere this year, having formed over 20 years ago, the act have pushed the boundaries of several genres by incorporating eclectic elements to death metal.

Post-punk legends Killing Joke are no strangers to Knebworth, having played at the inaugural event in 2009.

This year the original line-up will take to the stage after The Big 4’s grand finale on Friday.

Also confirmed are Four Year Strong, The Black Dahlia Murder and Black Tide.

Greek guitar guru Gus G, who is Ozzy Osbourne’s current axe man will appear with his power metal act Firewind.

Bringing tales of rum, wenches and high-seas rolling to the grounds of Knebworth are Scottish pirate-metallers Alestorm.

The band said: “We’re dead chuffed to finally be invited to Sonisphere. We’re gonna get drunk pirate style and party like it’s 1692.

“We might play a few songs too, if we’re not too hung over. See you all in the pit.”

All these acts will join heavy metal icons Metallica, Slayer and Motorhead for this year’s three-day show which takes place from July 8-10.

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