Unforgettable Concerts on Instagram: "🎤 The Big Four – Metallica, Megadeth, Slayer, Anthrax Live in Sofia, Bulgaria (June 22, 2010) On June 22, 2010, metal fans witnessed a moment that once felt impossible. Metallica, Megadeth, Slayer, and Anthrax — the full Big Four — shared the same stage at Vasil Levski National Stadium in Sofia, Bulgaria. It became one of the most important live events in metal history, uniting four defining bands for a single, era‑shaping performance. #Metallica #Megadeth