Outside Umberto Eco's office window in Milan looms the intimidating mass of Sforzesco castle, a reminder, with its towers and black birds, of various continental wars. Here once stood the 14th-century Castrum Portae Jovis – the Porta di Giove fortress – which was destroyed by the short-lived Aurea Republic of 1447. Between these walls, Leonardo Da Vinci and Donato Bramante once laboured; these ver