Leonardo da Vinci designed a canal lock to make canals easier for boats to navigate.
Leonardo is closely associated with improvements to the lock system on the Naviglio di San Marco in Milan. His work addressed the problem of moving boats between sections of canal at different water levels. A lock uses gates to isolate a chamber, allowing water to be added or released so a boat can rise or descend safely.
The system associated with Leonardo included mitre gates, whose angled leaves press more tightly together when water pushes against them. This was a practical refinement of canal engineering rather than a completely new invention of the idea of locks. Leonardo studied water movement, gates, channels, and hydraulic machinery extensively.
Leonardo’s hydraulic projects are sometimes credited too broadly. Canal locks existed before his work, and other engineers contributed to Milan’s waterways. His importance lies in observing, refining, and documenting mechanisms with exceptional technical detail. The Navigli canals helped transport materials and goods around Milan, making reliable water control economically valuable.