What type of bridge did Leonardo da Vinci design to support itself without permanent foundations?

Leonardo da Vinci designed a self-supporting bridge that could stand without permanent foundations.

His bridge concept used interlocking wooden elements arranged so that the structure’s own weight helped hold it together. This made it suitable as a rapidly assembled military bridge, especially for crossing temporary gaps or rivers.

The design appears in Leonardo’s notebooks, where he studied practical engineering alongside painting, anatomy, mechanics, and architecture. Modern builders have constructed models based on the same principle, confirming that the arrangement can be stable when correctly proportioned.

It is often confused with Leonardo’s revolving bridge, another portable military design. The self-supporting bridge is identified by its interlocking components and lack of piers or fixed supports; the revolving bridge was designed to pivot around a central support.