Leonardo da Vinci designed an armored fighting vehicle commonly called Leonardo’s tank. His 1480s design shows a broad, conical wooden cover strengthened with metal plates and fitted with cannons around its lower edge.
The vehicle was intended to move across a battlefield while protecting soldiers inside. Cranks connected to internal wheels would have allowed crews to propel it, although the surviving design has a mechanical problem: the proposed gears would make the wheels turn in conflicting directions unless the arrangement was corrected.
The machine was never built as a working Renaissance combat vehicle. It is often called a tank because its shape and battlefield purpose resemble later armored vehicles, but it was not a direct ancestor in engineering terms. Leonardo’s drawing is better understood as a conceptual siege machine combining armor, mobility, and artillery.