Leonardo da Vinci sketched a submarine for travel beneath the water’s surface.
His notes and drawings include ideas for a vessel that could operate underwater, with systems for controlling buoyancy and movement. Leonardo was cautious about recording some details, reportedly fearing that the design could enable secret underwater attacks. This has contributed to the submarine’s reputation as one of his more mysterious inventions.
The concept belongs to a long history of underwater-vehicle proposals rather than to the history of a tested Leonardo prototype. A submarine needs reliable control of buoyancy, pressure, air supply, and propulsion. Renaissance materials and knowledge made a practical, crewed submarine extremely difficult to build.
Leonardo’s submarine idea is distinct from his diving suit. A diving suit carries a person outside a vessel, while a submarine encloses its occupants in a pressure-resistant craft. Later inventors, including Cornelis Drebbel in the 17th century, built experimental submarines.