Leonardo da Vinci’s fighting vehicle most closely anticipated the modern tank.
Leonardo designed the vehicle around 1487 for the ruler Ludovico Sforza of Milan. Its conical, armored shell was intended to protect soldiers while they operated several light cannons. The machine was shown as a roughly circular platform with sloped armor, an arrangement that could deflect incoming projectiles.
The vehicle was supposed to move through a system of gears and cranks turned by people inside. A famous drawing appears to contain a gearing problem that would prevent the wheels from turning in the intended direction. Some historians think this may have been an intentional error that kept the design from being copied, while others regard it as a mistake.
Leonardo’s vehicle was never built as a Renaissance battlefield machine. It lacked an engine, suspension, and a workable crew layout. Its historical importance comes from combining armor, mobile firepower, and all-terrain movement in one early concept—features later associated with tanks.