The diocese of Milan is one of the largest in the world and is the only bishopric in the Occident (the only one in the Western world) to maintain its own Ambrosian liturgical rite that was introduced by Saint Ambrose, the patron saint of the city. This extensive and important diocese includes some of the major Catholic sites.
The first stop on this ecclesiastical itinerary is the iconic symbol of Milan, and the major Gothic building in Italy, the Duomo. The second is the first Western church built in the shape of a Latin cross, San Nazaro, followed by the paleochristian basilica of San Lorenzo Maggiore.
Shortly afterwards we come across two of the most ancient churches in Milan, Sant'Eustorgio and Sant’Ambrogio. The latter is the most important example of Romanesque architecture in Lombardy. The itinerary then leads to two Renaissance jewels: Santa Maria delle Grazie, a UNESCO World Heritage Site, and San Maurizio al Monastero Maggiore. The itinerary ends up with San Marco - the cradle of the Augustinians, San Simpliciano - one of the basilicas founded by Sant’Ambrogio, and the late-Renaissance church, Santa Maria della Passione.