Leonardo da Vinci designed a covered fighting vehicle that is commonly called an armored tank.
He drew the vehicle around 1487–1489 while working for Ludovico Sforza, duke of Milan. The design had a conical, turtle-like armored cover and multiple light cannons arranged around its lower edge. Inside, men would turn cranks connected to wheels, allowing the vehicle to move across a battlefield while shielding its crew.
The machine was never built in Leonardo’s lifetime, and it was not a modern tank. It had no engine, its armor was conceptual, and the weapons would have had limited effectiveness. A famous flaw in some reconstructions is that the internal gears appear to be arranged so the vehicle cannot move as drawn. Historians debate whether this was a mistake or an intentional feature to keep the design secret.
The nickname “Leonardo’s tank” is convenient but retrospective. The invention belongs to the era of Renaissance siege warfare, centuries before tracked armored vehicles became practical.