Leonardo da Vinci’s conical, crew-powered protective war machine was an armored vehicle.
Leonardo designed the vehicle around 1487 for Ludovico Sforza, the Duke of Milan. Its sloping outer shell was intended to deflect incoming projectiles, while several cannons projected through openings around the perimeter.
The machine was to be moved by men turning cranks connected to wheels. This made it more like a mobile armored artillery platform than a modern tank. The design’s conical upper covering also gave it a distinctive appearance unlike ordinary siege equipment.
A famous drawing appears to show the gears arranged in a way that would make the vehicle move backward. Some historians think this was an intentional error, perhaps to prevent the design from being used or to conceal Leonardo’s true mechanism. Modern reconstructions modify the gearing so the vehicle can travel forward.