This basilica was founded in 385 by order of St Ambrose, Bishop of Milan. Altered during the 10C and 11C, and remodelled in the 19C, the building has nonetheless retained the simplicity of early Christian churches, dominated by the use of brick. The façade has a fine marble doorway. Inside the church on the vault of the apse, note the Coronation of the Virgin by Bergognone (1481-1522).