What covered fighting vehicle did Leonardo da Vinci design?

Leonardo da Vinci designed an armored tank, a covered fighting vehicle powered by its crew.

His machine had a conical armored shell inspired partly by a tortoise’s protective shape. It was intended to carry several cannons and move across a battlefield while shielding the operators from enemy fire. The vehicle’s design appears in a notebook associated with Leonardo’s work for Ludovico Sforza in Milan.

The machine is often called Leonardo’s tank, but it was not a modern tank. It had no engine, tracks, or rotating turret. The crew would have turned internal cranks connected to wheels, and historians have noted that the surviving drawing appears to contain a mechanical problem that would prevent normal movement unless corrected.

The concept was therefore a theoretical Renaissance war machine, not a fielded weapon. Its significance comes from combining armor, mobility, and concentrated fire in one design.