What powered Leonardo da Vinci’s mechanical lion to walk?

Leonardo da Vinci’s mechanical lion was intended to walk using a clockwork mechanism.

Leonardo designed the lion for a court spectacle, probably involving King Francis I of France in 1515. Historical accounts say that the animal could move forward and open its chest, revealing fleurs-de-lis. The mechanism was based on gears, cams, and stored mechanical power rather than an external motor.

The original machine has not survived, so details of its construction remain uncertain. In 2019, an Italian engineer built a working reconstruction for an exhibition connected with the five-hundredth anniversary of Leonardo’s death. The lion is sometimes mixed up with Leonardo’s later mechanical knight, but these were different automata with different forms and intended presentations.