July 6 2011 – Metallica, Slayer, Anthrax and Megadeth – known collectively as The Big Four – warm-up for their appearance at this weekend's Sonisphere festival with a performance in Milan.
All four bands delighted fans at the Fiera Open Air Arena with career-spanning sets.
You can see pictures on Gigwise below.
Metallica, Slayer, Anthrax and Megadeth will headline the opening night of Sonisphere in Knebworth, which will also feature Slipknot and Biffy Clyro.
For more information about Sonisphere and all this summer's festivals, check out the Gigwise Festival Guide.
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