STAGE times for the Sonisphere 2011 music festival at Knebworth House have been revealed by organisers.

The three-day rock and metal event returns to the Hertfordshire stately home from Friday, July 8 to Sunday, July 10.

Thrash metal’s Big 4 of Metallica, Slayer, Megadeth and Anthrax will headline the opening day at the legendary rock venue.

British heavy metallers Diamond Head open proceedings on the Apollo stage on the first day at 3.15pm, with Anthrax playing at historic Knebworth House for the third year running from 4pm.

Megadeth play for an hour from 5.15pm and Slayer take the stage from 6.45pm to 7.45pm.

Metallica, who headlined the inaugural Sonisphere at Knebworth in 2009, will have a two-hour set from 8.30pm.

No acts play the Saturn stage on the Friday but groups alternate between the main outdoor stages, Saturn and Apollo, for the following two days, ensuring festival-goers don’t miss any of the bigger bands.

Sylosis kick off the music on the Saturday on the main stage at 11am.

Scottish rockers Biffy Clyro top the Apollo bill on the Saturday night with their first UK headline slot from 9.15pm.

Weezer play the same stage from 6.30pm, straight after American pop-punkers All Time Low, fresh from the success of their latest album Dirty Work, have come off Saturn.

The Mars Volta play their only UK festival on the Saturn stage from 7.40pm to 8.55pm.

Masked American metallers Slipknot close the Apollo stage on the Sunday night with an explosive 90-minute set starting at 9pm - their first appearance in this country since the death of founder member Paul Gray.

Earlier in the day there will be a two minute silence from 2pm across the festival site for the Slipknot bass player who died last year.

If Slipknot's not your thing, Irish rockers The Answer, who were AC/DC's special guests on their Black Ice World Tour and recently released live DVD 412 Days of Rock 'n' Roll, are on in Bohemia at the same time for an hour.

Comedian Bill Bailey headlines Saturn from 7.55pm to 8.40pm.

Bailey’s appearance clashes with Fozzy, the band of WWE wrestling legend Chris Jericho, who play the Jagermeister Stage from 8pm to 8.45pm.

Other Sunday highlights on the main stages include Limp Bizkit on Apollo from 6.45pm for an hour after Opeth have finished their set on Saturn.

Motorhead rock Knebworth for the first time at 4.45pm, while Mastodon also get an hour on Apollo from 2.50pm.

Ginger Wildheart also replace One Minute Silence in the Bohemia arena.

Following the main stage bands, music continues in the Bohemia tent until the early hours of the morning with late night spot and DJs.

On Sunday night there’s a mystery secret set in Bohemia from ‘Bat Sabbath’.

Here’s the full stage times for the Apollo, Saturn and Bohemia stages.

FRIDAY

* Apollo Stage *

Metallica 8.30pm - 10.30pm

Slayer 6.45pm - 7.45pm

Megadeth 5.15pm - 6.15pm

Anthrax 4pm - 4.45pm

Diamond Head 3.15pm - 3.45pm

* Saturn Stage *

No acts.

* Bohemia Stage *

A1 Bassline (DJ set) 2.15am - 3am

Fold (DJ set) 1.30am - 2.15am

Hayseed Dixie 12.30am - 1.30am

Killing Joke 11pm - midnight

Blood Red Shoes 8.10pm - 8.55pm

My Passion 7.10pm - 7.50pm

The Black Dahlia Murder 6.20pm - 6.50pm

Firewind 5.30pm - 6pm

Glamour of the Kill 4.40pm - 5.10pm

Lower Than Atlantis 4.50pm - 4.20pm

Japanese Voyeurs 3pm - 3.30pm

* Red Bull Bedroom Jam Stage *

Rolo Tomassi 8.30pm - 9pm

Protest the Hero 7.30pm - 8pm

Cerebral Ballzy 6.30pm - 7pm

Young Legionnaire 5.30pm - 6pm

Acoda 4.30pm - 5pm

Make This Relate 3.30pm - 4pm

* Jagermeister Stage *

Witchsorrow 10pm - 11pm

Flats 9pm - 9:30pm

The Defiled 8pm - 8.30pm

Black Breath 7pm - 7.30pm

Slam Cartel 6pm - 6.30pm

Hounds 5pm - 5.30pm

Decade 4pm - 4.30pm

Hammer of the Gods 3pm - 3.30pm

SATURDAY

* Apollo Stage *

Biffy Clyro 9.15pm - 10.45pm

Weezer 6.30pm - 7.30pm

You Me At Six 4.35pm - 5.35pm

Bad Religion 3pm - 3.45pm

Cavalera Conspiracy 1.25pm - 2.10pm

Architects 12.10pm - 12.40pm

Sylosis 11am - 11.30am

* Saturn Stage *

The Mars Volta 7.40pm - 8.55pm

All Time Low 5.40pm - 6.25pm

Sum 41 3.50pm - 4.30pm

Kids in Glass Houses 2.15pm - 2.55pm

Gallows 12.45pm - 1.20pm

Richard Cheese and Lounge Against the Machine 11.35am - 12.05pm

* Bohemia Stage *

Innerpartysystem (DJ Set) 2am - 3am

Tek One (DJ Set) 1am - 2am

The Sisters of Mercy 11.15pm - 12.45am

Paradise Lost 9.45pm - 10.45pm

Gojira 8.30pm - 9.15pm

Ginger Wildheart 7.25pm - 8.05pm

Periphery 6.15pm - 7pm

Pulled Apart by Horses 5.20pm - 5.50pm

Steve-O 4.20pm - 5pm

Jim Breuer 3.40pm - 4.10pm

Nick Helm 3.15pm - 3.35pm

Cherri Bomb 2pm - 2.30pm

Me vs Hero 1.10pm -1.40pm

Vintage Trouble 12.20pm - 12.50pm

While She Sleeps 11.30am - noon

* Jagermeister Stage *

Black Spiders 10.15pm - 11pm

Saint Jude 9pm - 9.45pm

Rival Sons 8pm - 8.30pm

Spycatcher 7pm - 7.30pm

The Crave 6pm - 6.30pm

Six Hour Sundown 5pm - 5.30pm

The Virgin Marys 4pm - 4.30pm

The Treatment 3pm - 3.30pm

Panic Cell 2pm - 2.30pm

Jettblack 1pm - 1.30pm

No Americana 12pm - 12.30pm

Sons of Icarus 11am - 11.30am

* Red Bull Bedroom Jam Stage *

Watain 9.45pm - 10.30pm

Rise to Remain 8.30pm - 9.15pm

Tek One 7.30pm - 8pm

Innerpartysystem 6.30pm - 7pm

TesseracT 5.30pm - 6pm

Revoker 4.30pm - 5pm

The Hype Theory 3.30pm - 4pm

Hill Valley High 2.30pm - 3pm

Page 44 1.30pm - 2pm

You and What Army 12.30pm - 1.30pm

The Suzukis 11.30am - noon

SUNDAY

* Apollo Stage *

Slipknot 9pm - 10.30pm

Limp Bizkit 6.45pm - 7.45pm

Motorhead 4.45pm - 5.45pm

Mastodon 2.50pm - 3.50pm

Parkway Drive 1.20pm - 1.55pm

Arch Enemy 12.10pm - 12.40pm

Volbeat 11am - 11.30am

* Saturn Stage *

Bill Bailey 7.55pm - 8.40pm

Opeth 5.50pm - 6.40pm

Airbourne 3.55pm - 4.40pm

In Flames 2.05pm - 2.45pm

2 Minutes Silence for Paul Gray 2pm - 2.02pm

House of Pain 12.45pm - 1.15pm

Black Tide 11.35am - 12.05pm

* Bohemia Stage *

Alfie (DJ Set) 12.15am - 1.10am

Stan SB 11.45pm - 12:15am

Bat Sabbath 10.55pm - 11.25pm

The Answer 9.25pm - 10.25pm

Four Year Strong 8.10pm - 8.55pm

Alestorm 7.10pm - 7.40pm

Cancer Bats 6.10pm - 6.50pm

Anberlin 5.15pm - 5.50pm

Sean Hughes 4.30pm - 5pm

Brendan Burns 3.55pm - 4.25pm

Jason Rouse 3.25pm - 3.55pm

Jason John Whitehead 3pm - 3.25pm

InMe 2.10pm - 2.40pm

Kylesa 1.20pm - 1.50pm

Turbowolf 12.30pm - 1pm

Howard Marks 11am - noon

* Jagermeister Stage *

Orange Goblin 10.15pm - 11pm

James Cleaver Quintet 9.15pm - 9.45pm

Fozzy 8pm - 8.45pm

Anterior 7pm - 7.30pm

Exit Ten 6pm - 6.30pm

Mad Dog 5pm - 5.30pm

Amplifier 4pm - 4.30pm

Demonic Resurrection 3pm - 3.30pm

Turbogeist 2.05pm - 2.35pm

Mojo Fury 1pm - 1.30pm

The Safety Fire 12pm - 12.30pm

Fletcher 11am - 11.30am

* Red Bull Bedroom Jam Stage *

Sonic Boom Six 7.30pm – 8.15pm

Don Broco 6.30pm – 7pm

Title Flight 5.30pm – 6pm

Dangerous 4.30pm – 5pm

Floods 3.30pm – 4pm

The Ocean Between Us 2.30pm – 3pm

Autumn in Disguise 1.25pm – 1.55pm

Feed The Rhino 12.30pm – 1pm

Arcane Roots 11.30am – noon