Leonardo da Vinci's armored vehicle design is commonly known by what modern name?

Leonardo da Vinci's armored vehicle design is commonly called Leonardo's tank. Drawn around 1487–1489, it was a conical, covered wagon intended to move across a battlefield while protecting soldiers inside.

The vehicle had sloping armor, which could deflect incoming projectiles, and multiple light cannons arranged around its lower perimeter. A crew inside would turn cranks connected to four large wheels. Leonardo's sketch appears to contain a mechanical error: the gears would make the wheels turn in opposite directions, so the vehicle could not move as drawn.

Many historians think the error may have been deliberate. Leonardo was seeking military employment and may have wanted to conceal details from readers of his notebooks. Modern reconstructions have corrected the gearing and shown that a working model can be built from the concept.

Calling it a “tank” is modern terminology; Leonardo himself described a covered fighting vehicle, not a tank in the twentieth-century sense.