Leonardo da Vinci designed an armored tank with sloped armor and a circular, turret-like body.
The machine appears in Leonardo’s military engineering drawings from the late fifteenth century. Its conical cover was intended to deflect incoming weapons, while openings around the lower edge allowed cannons to fire outward. Inside, people would turn cranks connected to wheels to move the vehicle.
Leonardo’s vehicle was never built for Renaissance warfare. Historians and engineers have also noted a famous problem in the surviving drawing: the gearing appears arranged so that the wheels would turn in opposite directions. Some researchers interpret this as a deliberate concealment of the design, while others see it as an error or an unresolved design issue.
Calling it a modern tank can be misleading because it had no engine, tracks, or enclosed crew compartment in the modern military sense. “Armored tank” is a convenient modern description of a heavily protected wheeled fighting vehicle.