What weapon did Leonardo da Vinci design with a very large bow mounted on wheels?

Leonardo da Vinci designed a giant crossbow with a very large bow mounted on a wheeled platform.

His drawing shows the weapon intended for military use, with wheels that would help move it and a mechanism for drawing back its powerful bow. The design reflects Leonardo’s interest in applying engineering principles to siege weapons.

The giant crossbow is generally understood as a design study rather than a confirmed, full-scale weapon that entered service. It is sometimes confused with Leonardo’s giant crossbow drawings that include different construction details, but the central idea is the same: a huge bolt-throwing bow supported by a mobile frame.

Leonardo also sketched other weapons, including multi-barreled artillery and a covered armored vehicle. These drawings show his interest in improving mobility, range, and the speed of reloading.