Big Four

The wheels for the seven 'Big Four' Sonisphere tour dates went into motion slowly but surely. First, Slayer signed on to do some shows with Megadeth in Australia and Japan. Then, the bands booked the North American Carnage dates, which were postponed when Slayer frontman Tom Araya needed neck surgery. During that time, Megadeth reunited with original bassist Dave Ellefson and headed out with Testament and Exodus. Once Megadeth were back at full speed, they were ready for the rescheduled Carnage dates with a full-force Slayer and newly-healed Tom Araya (don't take our word for it, though -- check out the group in peak form on the 'World Painted Blood' AOL Slayer Sessions video). And to put the icing on the cake, Anthrax reunited with mid-'80s vocalist Joey Belladonna for the first time since 2006.

All the while, Metallica did their thing, touring the globe, waiting for the curtain to fall for the seven Sonisphere shows, the first of which went down in Poland on June 16. "It's about f---ing time this happened," said Slayer guitarist Kerry King after the gig.

The event was special for a number of reasons. In the '80s, Metallica, Slayer, Megadeth and Anthrax constructed the blueprint for thrash metal, opening the floodgates for future waves of bands that included Testament, Overkill and Sepultura, among others. This marks the first time all four bands have shared the stage at once.

The 100,000 fans gathered at the Bemowo Airport in Warsaw, Poland knew they were witnessing history and will probably never forget the show. And each band, spurred on by the ecstatic audience and energetic performances of the other groups, gave its all for the sake of metal.

The Big Four lineup will play six more Sonisphere Festivals in the days ahead, including a show in Sofia, Bulgaria that will be broadcast via satellite on June 22 to more than 450 movie theaters in more than 140 markets in the U.S., Europe, Canada and Latin America. Delayed screenings will also take place in Australia, South Africa and New Zeland.