Bloodstock Open Air - The UK's No.1 Metal Festival - celebrates twenty one years over the next four days, when it kicks off today at Catton Park, Walton On Trent, Derbyshire, of which today's 'Bloodstock Rocks!' Tracks Of The Day showcase six of the great bands taking part, namely The Night Flight Orchestra, Ferocious Dog, Mother Vulture, Jinjer, Skarlett Riot and Sacred Reich.