Leonardo da Vinci’s military vehicle with a conical armored body and hand cranks was an armored tank.
Leonardo designed the fighting vehicle in the late 15th century, probably for Ludovico Sforza, the Duke of Milan. Its sloped, conical armor was intended to deflect enemy fire, while the platform carried several light cannons around its perimeter. A crew inside would turn cranks connected to wheels.
The vehicle is often called Leonardo’s tank, but it was not built for Renaissance warfare. The surviving drawing contains a famous apparent design problem: the gears seem arranged so that the wheels would turn in opposite directions. Some historians have suggested this could have been an intentional error to prevent the design from being copied, although that interpretation is not certain.
The concept resembles a modern tank in its armored, mobile fighting role, but it lacked an engine, steering system, and practical battlefield mobility. It remains one of Leonardo’s best-known military inventions.