Leonardo da Vinci designed an armored fighting vehicle commonly called Leonardo’s tank, powered by internal hand-operated wheels.
The vehicle was conceived as a covered, conical structure with sloping armor. Its outer shell was intended to deflect enemy weapons, while guns mounted around the lower edge could fire in several directions. Inside, operators would turn cranks connected to the wheels.
The design is often described as a tank, but it was not a modern tracked tank and was never built for Renaissance warfare. Historians have also noted a mechanical problem in the famous drawing: some gear arrangements would make the wheels work against each other. This may have been an error, an intentional flaw, or evidence that the plan was not fully developed.
Leonardo’s vehicle nevertheless demonstrates his interest in combining protection, mobility, and concentrated firepower. The first modern tanks appeared more than four centuries later during the First World War.