Leonardo da Vinci designed a tank-like armored vehicle as a mobile battlefield machine.
His fighting vehicle was a conical, turtle-shaped structure covered with armor and equipped with guns around its perimeter. Internal operators would turn cranks connected to wheels, allowing the vehicle to move while protecting its crew from enemy fire. Leonardo drew the design in the late fifteenth century while working for Ludovico Sforza in Milan.
The vehicle was never built for Renaissance warfare. A commonly repeated story says Leonardo deliberately included a flaw in the gearing so that the design could not easily be used, but historians cannot establish that this was his intention. The machine is called a “tank” because its enclosed, armored form resembles the broad concept of a modern tank, although it lacked an engine, tracks, turret, and the other features associated with twentieth-century armored vehicles.