Leonardo da Vinci designed an armored vehicle as a covered, turtle-shaped platform with cannons.
Leonardo sketched the vehicle around 1487–1490 while working for Ludovico Sforza in Milan. Its conical wooden cover was reinforced with metal plates and intended to protect soldiers while they operated guns positioned around the platform. The design used wheels and was meant to move across a battlefield.
The machine is often called Leonardo’s tank, but that modern label can be misleading. It was not a functioning modern tank, and no full-size original vehicle survives. The surviving drawing shows a compact fighting machine rather than a detailed production blueprint.
A famous problem is that the vehicle’s internal gears appear to be arranged so that it could not move as drawn. Some historians think this was an intentional error that concealed the design, while others regard it as a mechanical mistake. Modern reconstructions have demonstrated that revised gearing can make the concept mobile.