Leonardo da Vinci sketched an armored tank as a covered, conical vehicle powered by hand-operated cranks.
The design appears in Leonardo’s papers from around 1487–1489. Its sloped outer shell was intended to deflect enemy fire, while a ring of guns projected through openings around the vehicle. Inside, operators would turn cranks connected to the wheels, allowing the machine to move across the battlefield.
The vehicle is commonly called Leonardo’s tank, but it was not a modern tank. It had no engine, tracks, turret, or documented battlefield trial. The famous drawing also appears to contain a mechanical problem: if the gears are arranged exactly as shown, the wheels would work against one another. Some historians think this may have been deliberate, preventing the design from being copied.
The concept illustrates Leonardo’s combination of military engineering, mechanics, and protective architecture.