Leonardo da Vinci designed an armored tank, usually called Leonardo’s fighting vehicle, with a circular armored body and multiple cannons.
The vehicle appeared in a drawing from about 1487 and was shaped like a covered, conical platform. Small cannon were arranged around its perimeter so they could fire in several directions. The machine was intended to move using manually operated wheels and gears inside the protective shell.
Although often called the first tank, Leonardo’s vehicle was a design rather than a deployed armored fighting vehicle. Historians have also noted a possible gearing problem in the surviving drawing: two gears appear arranged so that the vehicle would not move as intended. Some researchers think this may have been deliberate, perhaps to prevent the design from being easily used.
Its sloped armor and all-around firepower resemble later armored vehicles, but it lacked an engine, reliable steering, and a practical power source.