Leonardo da Vinci’s heavily armored military vehicle designed around 1487 is commonly called Leonardo’s tank.
Leonardo drew the machine as a covered, conical structure fitted with guns around its lower edge. Crews inside would turn cranks connected to wheels, allowing the vehicle to move while shielding the occupants from enemy fire. The design is often described as an early tank concept, although it was never built as a working battlefield vehicle during Leonardo’s lifetime.
The word “tank” is modern: Leonardo did not use that English term, and the vehicle was not a practical prototype in the modern engineering sense. Historians also note a likely gearing problem in the surviving drawing, because the mechanisms appear arranged in a way that would prevent normal movement. A later reconstruction corrected or interpreted those details differently.
Leonardo’s sketch belongs to his broader work for military patrons, who valued fortifications, artillery, bridges, and siege equipment. Its importance lies chiefly in combining armor, mobility, and concentrated firepower in one proposed machine.