Which Leonardo da Vinci transport design is often called the first automobile?

Leonardo da Vinci’s self-propelled cart is often called the first automobile.

Leonardo designed the cart around 1478–1480. Unlike a normal wagon pulled by animals, it was powered by wound-up springs hidden inside its body. Gears transferred the spring energy to the wheels, while a steering mechanism helped determine its direction.

The cart was probably intended for theatrical performances or court pageants rather than everyday transportation. It could move without a horse, but its range would have been limited by the energy stored in its springs. Leonardo’s surviving drawings do not provide every construction detail, so modern reconstructions have helped test how the mechanism may have operated.

Calling it the first automobile is a popular shorthand, not a claim that it resembled a modern car in every respect. It had no combustion engine, brakes, or passenger-focused design. Its importance is that it represents an early documented vehicle propelled by an onboard mechanical power source.