The 17th century church of Santi Ambrogio e Carlo, better known as San Carlo al Corso, is dedicated to two great bishops of Milan, St Ambrose and St Charles Borromeo. The church was designed and built by Onorio Longhi (1568-1619) and completed by his son Martino Longhi the Younger (1602-60). Its grand dome, a distinguished feature of the Roman skyline, is the work of Pietro da Cortona (1596-1669).
The Baroque interior of this very large church (72 by 54 metres) is sumptuously decorated. The fresco in the vault of the nave depicts the Fall of the Rebel Angels (1677-79) and is the work of Giacinto Brandi (1621-91). The frescoes in the vault of the sanctuary are also by Brandi. The high altar, however, is the work Carlo Maratta (1625-1713) and depicts the MadonnaPresenting of St Ambrose and St Charles Borromeo to Christ. A figure below the feet of Christ holds a tablet bearing a single word Humilitas, the virtue for which St Charles was famous. San Carlo al Corso is the only church in Rome to have an ambulatory (a walkway behind the high altar). There you will find a niche with a reliquary containing the heart of St Charles Borromeo (1538-84), who was canonised in 1610.