It looks like the rumors are true and the big four of thrash metal will finally share a stage for the first time in history.

Metallica, Megadeth, Anthrax and Slayer will share a stage in Warsaw, Poland as part of the Sonisphere Festival on Wednesday, June 16 at Bemowd Airport.

If you live in the U.K. and want to make the trip over to Poland for this historic show, you can buy tickets to the upcoming Knebworth concert, and get a free ticket to the Polish show.

According to the Knebworth site, "To make sure as many people as possible can witness this historic event, the offer has been extended so that you are GUARANTEED to get a Poland ticket if you buy a Sonisphere Weekend Knebworth ticket before 31ST DECEMBER 2009 (midnight)"

"The Big Four" are icons of thrash metal from its beginnings back in the early 80s when they took influences from punk and the new wave of British heavy metal to create a beautiful new sound.