What Leonardo da Vinci military vehicle was an armored wagon with cannon openings?

Leonardo da Vinci’s armored military vehicle was Leonardo’s armored tank, also called his fighting vehicle.

Leonardo sketched the vehicle around 1487–1489 for Ludovico Sforza, duke of Milan. It had a conical, turtle-like armored shell intended to protect soldiers inside. Several light cannons projected through openings around the lower edge, allowing the crew to fire in multiple directions while remaining shielded.

The vehicle was designed to move using manually operated wheels connected to internal gears. Modern reconstructions have shown that the mechanism as drawn would not work without correction: two gears appear to turn in incompatible directions. Historians commonly interpret this as either a drafting error or a deliberate flaw intended to keep the design from being copied.

Calling it a “tank” is a modern comparison, not Leonardo’s own term. The drawing predates twentieth-century armored tanks by centuries and represents an early concept for an armored, mobile artillery platform.