Leonardo da Vinci sketched an odometer for measuring distances traveled.
His design used a wheel that turned as a vehicle moved. A counting mechanism recorded the wheel’s rotations, allowing the operator to estimate how far the vehicle had traveled. The arrangement is an early example of applying mechanical counting to transportation.
Leonardo’s odometer was associated with surveying and engineering work, where measured distance was essential for planning roads, canals, fortifications, and construction. It was not an electronic device and did not measure distance directly in the modern digital sense.
An odometer differs from a speedometer: an odometer records total distance, while a speedometer indicates speed. Leonardo’s design belongs to the long history of mechanical distance-measuring devices and reflects his interest in combining wheels, gears, and counting systems.