Leonardo da Vinci designed an armored car, a conical military vehicle covered by sloped armor and armed with cannons.
His drawing, usually called Leonardo's fighting vehicle, shows a large circular platform resembling an overturned cone. Small cannons project through openings around its perimeter, while internal operators would turn the vehicle using cranks connected to wheels. The sloped exterior was intended to deflect incoming projectiles and protect the crew.
The design was created in the late fifteenth century, when Italian states were competing for military technology. It was not built in Leonardo's lifetime, and several practical problems would have made operation difficult. The proposed mechanism may even have included a deliberate flaw that prevented the vehicle from moving unless its gears were modified.
Although commonly called a tank, the historical term is armored car or fighting vehicle. It should not be confused with the modern tracked tank, which was developed during the First World War and used a different propulsion system.