The name of Santa Maria in Domnica comes from the word "dominicum," one of the ways Christian churches were named in ancient Rome. This church was constructed in the 7th century on the ruins of the building used by the 5th Cohort of Guards. It was entirely reconstructed in the 9th century by Pope Pascal I and renovated yet again in 1513 by Cardinal Giovanni de' Medici, the future Pope Leo X.

Inside, the columns, dating back to imperial Rome, divide the basilica into the usual 3 naves. The mosaics are from the 9th century. In front of the church is the Navicella Fountain, designed by Andrea Sansovino for Giovanni de' Medici. The ship used for the fountains appears to be an ex-voto offering to the goddess Isis by sailors from Cape Miseno who had survived a shipwreck.
As you go down the street towards the valley of the Colosseum, you can see on your left the walls that once belonged to a temple which Agrippina presented to the Emperor Claudius, her husband. These walls were later annexed by Nero for the Nymphaeum of his Domus Aurea.