Leonardo da Vinci sketched a conical armored fighting vehicle commonly called a tank.
The design, produced around 1487, resembles a covered, circular platform with sloping armor and multiple small cannons around its perimeter. Inside, men were supposed to turn cranks connected to wheels, allowing the vehicle to move across a battlefield while protecting its crew.
Leonardo's fighting vehicle was not a modern tank. It had no engine, its weapons were small guns rather than a turret-mounted cannon, and historians debate whether the famous drawing contains an intentional mechanical error. As drawn, some internal gears would rotate in conflicting directions, though a simple correction could make the drive system work.
The vehicle demonstrates Renaissance interest in combining armor, mobility, and firepower. The first operational tanks appeared more than four centuries later during World War I, after engines and industrial manufacturing made such vehicles practical.