Leonardo da Vinci designed an armored tank-like military vehicle driven by many internal wheels.
His fighting-vehicle design dates from the late fifteenth century and resembles a low, conical turtle shell. The outer covering was intended to protect crew members from enemy fire, while a ring of guns projected through openings around the vehicle. Inside, several men would turn cranks connected to the wheels.
The surviving drawing contains a mechanical problem: the gears appear to be arranged so that the vehicle would move backward if built exactly as shown. Some historians think this was an intentional error to keep the design secret, while others regard it as a drafting mistake. There is no evidence that Leonardo’s vehicle was constructed or used in battle.
It was not a modern tank in the technical sense. Twentieth-century tanks used engines, tracks, armor, and coordinated military tactics. Leonardo’s concept is nevertheless an early example of combining armor, mobility, and onboard weapons in one vehicle.