The Romanesque church of San Babila, built around the XI century, originally had three naves and three apses. The largest central nave was divided into three bays, in the second of which was an octagonal lantern dome. It was devoid of side chapels and sacristy.
The first modifications were in the Visconti era, with the consecration of two altars and the construction of the sacristies.
Following the visit of Archbishop Visconti in 1591 it was decided to carry out more radical works considering the poor state of the church. In fact, the restoration in the Baroque period led to the demolition of the Romanesque facade to add a bay to the church, plus, the demolition of the apses.
However, the reconstruction was not definitive. In the early XX century the Baroque style renovations were mercilessly demolished to make space for the neo-Romanesque changes. Over time the interior has acquired windows by Bertini, pictorial decorations of Pogliaghi and Cavenaghi and the main altar by Moretti.
Other works were carried out at different times: the Paleochristian inspired baptistery and the new chapel of the Addolorata replacing one destroyed by bombing during the Second World War.The history of the foundation of the church of San Babila has been the subject of numerous debates, but it now seems that there is a consensus of opinion. According to legend San Babila was the first church built in Milan in 46 AD upon the site of a pagan temple dedicated to the Sun. The same legend says that it was erected by S. Barnaba who would have celebrated his first Mass there after entering the city.
In fact, the most ancient data testifying the existence of a church dedicated to San Babila dates from the XII century and confirms that it was built more recently by the priest Nazario Muricola. Subsequent excavations for its restoration confirm this latest version.