Begun in the early 17C, this church boasts a grandiose Baroque façade, like a theatre set, with its two towers and its angels. With a centred layout, it is dominated by a dome with fine proportions. Inside, richly decorated with marble, frescoes and gilding, there are numerous Lombard paintings from the 18C. The pulpit and high altar are particularly impressive. The Cappella della Natività has a remarkable painting by Procaccini and frescoes by il Moncalvo.