Leonardo da Vinci’s armored military vehicle with a conical body is commonly called an armored car.
Leonardo designed the vehicle in the late 15th century, probably for Ludovico Sforza, the ruler of Milan. Its sloped, conical covering was intended to deflect enemy fire, while openings around the structure allowed mounted guns to fire in multiple directions. The vehicle was powered by men turning cranks connected to wheels.
The design is often called Leonardo’s tank, but that modern label can cause confusion. It was not a modern tank, and it was never built or used in battle during Leonardo’s lifetime. A commonly discussed problem is that the gear arrangement in the surviving drawing appears to make the vehicle move backward. Historians debate whether this was an error, deliberate sabotage, or an incomplete design.