July 8-10 2011 – The Sonisphere Festival in Hertfordshire welcomed headline performances from The Big Four – Metallica, Slayer, Megadeth and Anthrax – Biffy Clyro and Slipknot.
Taking place at Knebworth House, thousands of music fans also held a two minute silence for Slipknot's late bassist Paul Gray, who died last year.
Other performances over the weekend came from Limp Bizkit, Weezer, Airbourne, Sum 41, The Mars Volta and Pulled Apart By Horses.
Check out Gigwise's best bits in pictures below.
For more information about the Sonisphere festival and all this summer's festivals, check out the Gigwise Festival Guide.
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