Not all of Rome’s treasures are in museums and galleries in the centre. A short bus journey to a residential neighbourhood slightly north of the centre takes you to the Mausoleum of Santa Costanza, one of the most beautiful buildings in Rome.

Santa Costanza is an ancient mausoleum that was later converted into a church. It was originally believed to have been built by Constantine I for his daughter Costantina, but experts now believe that it was built by Emperor Julian for his wife Helena, who was also one of Constantine’s daughters. But you don’t need to get too bogged down in Ancient Roman family trees to appreciate Santa Costanza. The few people who know about this place come to see the art – exquisite 4th-century mosaics that cover the ceiling. Pagan imagery was surprisingly common in early Christian art, and the mosaics of Santa Costanza depict scenes of cherubs harvesting among swirling vines and floral patterns.

Entrance is free, but you’ll need to donate some change to illuminate the mosaics. While you’re there, make sure you visit the Basilica of St Agnes next door (St Agnes is buried under the altar). There are also guided tours of the catacombs. 

To reach Santa Costanza from central Rome, simply take the metro B to Sant’Agnese-Annibaliano, or take the 90 bus from Termini and get off at the stop Nomentana/XXI Aprile.