Leonardo da Vinci’s armored, conical military vehicle powered by crew-operated wheels is commonly called a tank.
Leonardo designed the fighting vehicle in the late 15th century, probably around 1487. Its sloping armor was intended to deflect enemy fire, while a circular platform carried several light cannons. The machine would have been moved by people turning cranks connected to its wheels.
The concept was never built for Renaissance warfare, and the surviving sketch contains a mechanical problem: the gearing appears to make some wheels turn in opposing directions. Historians have debated whether this was an error, a deliberate concealment, or an unfinished design.
Leonardo’s vehicle was not a tank in the modern technical sense. It had no engine, tracks, or completed production history. The name is a retrospective comparison based on its armored enclosure, mobile gun platform, and battlefield purpose.