Leonardo da Vinci designed a tank-like armored fighting vehicle in 1487, often called the first tank.
His design used a conical wooden shell reinforced with metal plates. The vehicle was intended to move with the help of several men turning cranks inside it, while cannons positioned around the lower edge could fire in multiple directions.
The machine was never built in Leonardo’s lifetime. Modern discussions often call it a tank, but that name belongs to much later military technology, especially the tracked vehicles introduced during World War I. Leonardo’s machine had wheels and human-powered propulsion rather than an engine or tracks.
A commonly noted problem is that the surviving design appears to contain gearing that would make the vehicle move backward. Historians debate whether this was an intentional flaw, a drawing error, or evidence that the design was not fully developed.