Leonardo da Vinci sketched an armored tank as a conical, turtle-like fighting vehicle.
His design, usually called Leonardo’s fighting vehicle, appears in notes from the late fifteenth century. It consisted of a circular wooden platform covered by sloping armor plates, with cannons arranged around its outer edge. The sloped surfaces were intended to deflect incoming projectiles, while crews inside would operate the weapons.
The vehicle was supposed to move using manually turned cranks connected to wheels. A famous drawing contains a gearing problem that would prevent the vehicle from moving as shown. Historians debate whether that error was accidental or deliberate, perhaps because Leonardo did not want the design to be immediately usable by a patron’s rivals.
It was never built or used in Renaissance warfare. The modern term “tank” is convenient, but Leonardo’s machine was a conceptual armored fighting vehicle rather than a modern tracked tank. Its circular layout and multiple guns distinguish it from later tanks.