What type of vehicle did Leonardo da Vinci sketch with armor and cannons?

Leonardo da Vinci sketched an armored tank-like fighting vehicle with cannons.

The design, created around 1487, was a conical, covered vehicle mounted on wheels. Its sloping armor was intended to deflect enemy fire, while openings around the lower edge allowed several cannons to be aimed outward. Leonardo imagined the machine being moved by people turning internal cranks.

The vehicle was never built in the Renaissance. Modern reconstructions have shown that the original drawing contains a mechanical problem: if the gears are arranged exactly as Leonardo depicted them, the wheels would work against one another. Some historians think this may have been deliberate or may reflect an error in the surviving design.

It is often called Leonardo’s tank, but it was not a modern armored vehicle. It had no engine, turret, or tracked drive. Its importance lies in its early combination of mobile protection and artillery.