"Architecture is a crystal. Love architecture for the abstract, allusive and figurative forms that enchant our spirit and enrapture our thoughts." So wrote Gio Ponti, one of Milan's most famous architects and creator of the inimitable Pirelli Tower. Milan is brimming with architectural treasures, both traditional and hyper-modern, which are best discovered on foot. Admire the futuristic buildings of Porta Garibaldi, where the "spire" of César Pelli's UniCredit Tower dominates Piazza Gae Aulenti. Not too far away, you can find some great examples of 1960s architecture, including "ringhiera" houses with their inner courtyards, as well as neoclassical and Art Nouveau buildings. Continue to discover the hanging gardens of Stefano Boeri's Bosco Verticale, recognised as the most beautiful skyscraper in the world in 2014. Finish with a lunch in a typical restaurant, immersed in the heady aroma of saffron risotto. An open-air tour to learn about the history and evolution of Italy's most glamorous city.