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Leonardo worked in Milan from 1482 until 1499. He was commissioned to paint the Virgin of the Rocks for the Confraternity of the Immaculate Conception and The Last Supper for the monastery of Santa Maria delle Grazie. In the spring of 1485, Leonardo travelled to Hungary on behalf of Sforza to meet king Matthias Corvinus, and was commissioned by him to paint a Madonna. Leonardo was employed on many other projects for Sforza, including the preparation of floats and pageants for special occasions, a drawing and wooden model for a competition to design the cupola for Milan Cathedral (which he withdrew), and a model for a huge equestrian monument to Ludovico's predecessor Francesco Sforza. This would have surpassed in size the only two large equestrian statues of the Renaissance, Donatello's Gattamelata in Padua and Verrocchio's Bartolomeo Colleoni in Venice, and became known as the Gran Cavallo. Leonardo completed a model for the horse and made detailed plans for its casting, but in November 1494, Ludovico gave the bronze to his brother-in-law to be used for a cannon to defend the city from Charles VIII.