What did Leonardo da Vinci design to protect soldiers while advancing across a battlefield?

Leonardo da Vinci designed an armored fighting vehicle to protect soldiers while advancing across a battlefield.

His design, drawn around 1487–1489, resembles a low, conical tower mounted on wheels. Several light cannons projected through openings around its perimeter, allowing the crew to fire in different directions while protected by sloping armor.

The vehicle is often called Leonardo’s tank, but that name is modern: the 15th-century drawing did not use the word “tank,” and the machine was never built in Leonardo’s lifetime. Its intended movement also presents a famous engineering problem, because the original internal gearing appears to make the wheels turn in opposite directions. Some historians think this may have been an intentional mistake or a drawing error.

The concept is therefore best understood as an early armored fighting-vehicle design, not a working Renaissance tank. Modern tanks developed much later, especially during World War I, with engines, continuous tracks, and purpose-built armor.