Leonardo da Vinci’s armored fighting vehicle is commonly called Leonardo’s tank.
Leonardo sketched the vehicle in 1487. It had a conical, turtle-like shell covered with metal plates and a ring of light cannons around its sides. The design was intended to protect soldiers while allowing them to fire in multiple directions.
The vehicle was supposed to move through the effort of men turning cranks connected to wheels. A well-known drawing contains a gear arrangement that appears to work against the vehicle’s movement. Some historians think this may have been an intentional error that prevented the design from being built or copied without Leonardo’s approval.
The machine was never produced as a battlefield vehicle. Calling it a tank is a modern label; Leonardo described an armored war machine centuries before the motorized tanks of the First World War.