Leonardo da Vinci's Best Military Invention: The Aerial Map

Leonardo da Vinci attaches himself to Cesare Borgia, a strongman in need of a military engineer and cartographer. In the villages seized by Borgia’s army, Leonardo surveys the fortifications, paces off distances and uses a compass to determine the measurements. He also gathers topographical data and draws meticulous maps featuring the hills and mountains, lakes and rivers of eastern Tuscany.