What Leonardo da Vinci invention is often described as the earliest known self-propelled vehicle?

Leonardo da Vinci’s self-propelled cart is often described as the earliest known self-propelled vehicle.

Leonardo designed the cart around 1478–1480. Unlike a normal wagon pulled by animals or pushed by people, it was intended to move through stored energy in coiled springs. A system of gears transferred that energy to the wheels, while steering could be set in advance.

The cart was probably designed for theatrical or ceremonial use rather than transportation. It could travel along a predetermined path, making it suitable for carrying a moving figure or stage effect. The surviving drawing leaves important construction details open to interpretation.

The machine was not powered by an engine in the modern sense. Reconstructions have shown that a spring-driven version can move, but they do not demonstrate exactly how Leonardo intended every part to work. It is best understood as an early mechanical vehicle, not a modern automobile.