What oversized weapon did Leonardo da Vinci sketch with multiple bows?

Leonardo da Vinci sketched a giant crossbow with multiple bows.

The design appears in Leonardo’s engineering studies from the late fifteenth century. It was intended as a siege weapon, with a very large bow mounted on a wheeled base. Leonardo’s drawings show a broad frame and mechanisms for drawing the bowstring, aiming the weapon, and supporting its considerable weight.

The proposed weapon was far larger than an ordinary handheld crossbow. Its scale was meant to increase the range and psychological impact of the projectile, although the design’s practical performance remains uncertain. Leonardo frequently explored military machines for patrons who wanted stronger fortifications and more effective battlefield equipment.

The giant crossbow was never a standard battlefield weapon. It belongs to the same group of ambitious military concepts as Leonardo’s armored vehicle and multi-barrel gun. Its importance lies in the way Leonardo combined mechanical engineering, transport, and weapon design in a single machine.