Basilica di Santa Maria in Trastevere 

The Basilica was probably the first official place of Christian worship in Rome. According to legend, it was commissioned by Pope Calixtus I in the 3rd century and was finished by St. Julius I in 340.

Rebuilt during the pontificate of Pope Innocent II, it later had decorations and restorations, including notable ones promoted by Pope Clement XI (1702) and Pope Pius IX (1870), but without substantial alterations to the church.

Many parts of the church date from the 12th century; important are the mosaics, especially those on the facade and those in the apse, made by Pietro Cavallini and depicting the "Life of the Virgin." On the outside stands the bell tower, with a square base, built in the 12th century.

The portico was remodeled in 1702 by Carlo Fontana and now houses fragments of friezes and ornaments from the ancient basilica, as well as Christian epigraphs, and is surmounted by a balustrade decorated with statues of four popes.

The basilica interior has three naves divided by twenty-two ancient granite columns of various diameters, all with Ionic and Corinthian capitals, probably from the Baths of Caracalla.

The very rich ceiling has carved and gilded lacunars with polychrome backgrounds, designed by Domenichino (1617) with the image of "The Assumption" in the center. In 1860, the floor was almost completely reconstructed by architect Vespignani with floor mosaics typical of the 13th century. In the basin and apse arch, in addition to mosaics with stories of the Virgin by Pietro Cavallini (1291), there are mosaics made around 1140, after the death of Pope Innocent II, who is depicted there with a model of the church.

FONTE: https://www.turismoroma.it/it/luoghi/basilica-di-santa-maria-trastevere