Leonardo da Vinci designed an armored tank with conical protective plates and cannon openings.
Leonardo recorded the design around 1487–1489 while working in Milan for Ludovico Sforza. The vehicle was shaped like a large, covered turtle and was intended to move across a battlefield while protecting the men inside. Its sloping armor could deflect projectiles, and cannons were arranged around the lower perimeter.
The machine was to be moved by people turning cranks connected to wheels. A famous drawing contains a gear arrangement that appears to make the vehicle impossible to drive as shown. Historians commonly interpret this as either a deliberate error, a drafting mistake, or a concealed safeguard.
Leonardo’s machine was not a modern tank and was never built in his lifetime. It was a Renaissance concept for a mobile artillery platform, not a tracked vehicle powered by an engine. Modern reconstructions usually alter the gearing so it can move.