Beside the Church of the Twelve Apostles is the 40-ton Emperor Cannon. Its 890 mm bore (35 inch caliber) makes it the world's largest cannon still in existence. It was cast in 1586 by Andrei Shchokhov and never fired. (The largest was smelted at an arms factory in Perm in the 1530s and used to defend Russia against the Tartars; it was fired over 300 times.) A likeness of Fedor I is on the barrel. The decorative iron cannon balls (weighing one ton each) were cast in the 19th century.