Leonardo da Vinci sketched an armored tank as a cone-shaped military fighting vehicle.
His fighting vehicle drawing, usually dated to the late fifteenth century, shows a broad conical shell mounted on wheels. The machine was intended to carry men inside who could operate weapons through openings in the armor. Leonardo’s notes describe a vehicle that could move toward an enemy while protecting its crew from attack.
The design is often called Leonardo’s tank, although it was not a modern tank and was never built for battle. A commonly discussed problem is that the drawing’s internal gears appear to make the wheels turn in opposing directions. Some historians think this may have been deliberate, possibly to prevent the design from being copied, while others view it as an error. The vehicle predates twentieth-century tanks by centuries and belongs to Renaissance studies of fortification, mechanics, and military engineering.