What device did Leonardo da Vinci design for exploring underwater?

Leonardo da Vinci designed a diving suit for exploring underwater environments.

His proposed suit included a sealed covering, a breathing system, and tubes leading to the surface. The concept was intended to let a diver remain underwater while receiving air through a pipe. Leonardo’s notes also considered practical details such as visibility, movement, and the danger of the breathing tube being damaged.

The design belongs to Leonardo’s broader study of military engineering and water operations. He imagined underwater equipment that could support covert activity near enemy ships, although there is no reliable evidence that his suit was built and successfully used in Renaissance Italy.

The invention is often confused with a submarine or diving bell. Those are different technologies: a submarine encloses a vessel, while a diving bell provides a chamber of air. Leonardo’s proposal was a wearable diving suit.