Leonardo da Vinci designed an armored vehicle with sloped armor and multiple guns as a proposed military machine.
The vehicle was shaped like a covered, conical tortoise. Its armor was intended to protect the crew, while several light cannons projected through openings around the perimeter. The machine was to move on wheels powered by men operating internal cranks.
Leonardo described the vehicle in a late-fifteenth-century design. It was never built for Renaissance warfare, and historians note that the surviving design contains a gear arrangement that would prevent the vehicle from moving if constructed exactly as drawn. This may have been an error or deliberate concealment.
Calling it a modern tank is convenient but technically imprecise. The design lacked an engine, tracks, and modern armor technology. “Armored vehicle” best describes Leonardo’s proposed machine without implying that it was an operational tank.