Leonardo da Vinci designed his wheeled armored vehicle to resemble a turtle.
The fighting vehicle was a conical, armored platform with sloping protective panels. Its broad shape was intended to deflect incoming projectiles, while cannon openings around the perimeter would allow weapons to fire outward. The vehicle’s appearance and protective shell led to its comparison with a turtle.
Leonardo’s design dates from the late fifteenth century and was intended for military use. Several men inside would turn cranks connected to the wheels. Modern reconstructions have pointed out a famous mechanical problem: if the internal gearing is arranged exactly as shown, the wheels would not turn in the intended direction. Some historians think this may have been a deliberate flaw or an error in the drawing.
The vehicle was never documented as having been built or used in battle. It remains one of Leonardo’s best-known military engineering concepts, not an operational tank.