Metallica, Slayer, Megadeth and Anthrax, collectively known as The Big Four of thrash metal, are set to perform on the same stage for the first time in music history as part of the Sonisphere Festival's tour of Europe. The four heavy metal legends are set to play Sonisphere in Warsaw on June 16th and Prague on June 19th.

Metallica drummer Lars Ulrich said, ""Who would have thought that more than 25 years after its inception, thrash metal's big 4 would not only still be around and more popular than ever, but will now play together for the first time. "

Anthrax guitarist Scott Ian claims the tour ends "26 years of expectation."
"I believe not only will we live up to the expectations, we will shatter them!! No other four bands as influential as the four of us have ever done this. Imagine if the Beatles, Stones, the Who and Zeppelin had done shows? Or Sabbath, Priest, Maiden, Motorhead?...That's how big I feel this is."

Meanwhile, Medadeth frontman Dave Mustaine described the tour as " a once-in-a-lifetime opportunity for heavy metal fans to see the four greatest heavy metal bands in American history back together on one stage", while Slayer guitarist Kerry King said "It's about f***ing time this happened, and about time the fans finally get what they want."

Sonisphere Festivals tour to the following cities in summer 2010:
Knebworth, UK – 30 July – 1st August
Warsaw, Poland – 16th June
Prague, Czech Republic – 19th June
Stockholm, Sweden – 7th August
Pori, Finland – 7th & 8th August
Zurich, Swizterland – 18th June
Sofia, Bulgaria – 22nd & 23rd June
Athens, Greece – 24th June
Bucharest, Romania – 25th-27th June
Istanbul, Turkey – 25th-27th June
Barcelona, Spain – 10th July

At the moment the big four are only confirmed to play together in Warsaw and Prague, but more announcements are expected to come soon. Mastodon are also confirmed for both these dates. Those who purchase their ticket for the UK date in Knebworth (headlined by Iron Maiden and Rammstein) before December 31st will received a free ticket for the Warsaw festival. For more details of this promotional offer visit http://uk.sonispherefestivals.com/