The square owes its name to the Basilica of Santa Maria in Trastevere.

A fountain of the same name, which is one of the most antique in Rome, is in the middle of the square. It is said that one of its sources was built in 2 b.c.

Today’s look is attributed to Bramante who restored it between 1496 and 1501.

In the evening it becomes one of the centres of Roman nightlife: it is invaded by tables belonging to the different bars and pubs and crowded with young people, who meet up on the steps of the fountain.