Leonardo da Vinci sketched an armored tank as a covered, circular fighting machine powered by cranks.
The design appears in Leonardo’s notebooks from the late 15th century. It has a conical armored shell inspired partly by a tortoise’s protective shape, with cannons arranged around the lower edge. Several men inside would turn cranks connected to wheels, moving the vehicle across a battlefield.
The vehicle was never built for Leonardo’s patrons and was not a modern tank. It had no engine, and its armor and weight would have made movement difficult. A commonly discussed problem is that some drawings show the internal gears arranged so the wheels would turn in opposite directions. Historians debate whether that was an error, a deliberate concealment, or an untested detail.
Leonardo’s fighting vehicle belongs to a larger group of military designs, including bridges, artillery, and fortifications. Its importance is conceptual: it combined mobile protection, concentrated firepower, and mechanical propulsion centuries before tracked armored vehicles appeared.