It is impossible to discuss a history of architectural sketches without an example from Leonardo da Vinci, whose numerous sketchbooks reveal the genius of an architect, painter, sculptor, and inventor. Although he built or finished very little architectural work, he proposed designs for domed, centrally planned churches, fortifications, numerous mechanical inventions, and buildings in various scales from chapels to palaces to cities. At an early age he started in the workshop of painter Andrea del Verrochio. Throughout his career, Leonardo worked as a military engineer in Milan, in his own studio in Florence, and later in his life, on projects for King Louis XII in France. It was in Amboise, France, where he died in 1519. His works that remain include extensive sketchbooks, some sculpture, and paintings such as the Mona Lisa, Virgin of the Rocks and the fresco The Last Supper in San Maria delle Grazie, Milan. A consummate observer, Leonardo took an empirical approach to satisfy his ...