Was the first Cathedral of Genoa, it was built between the 4th and 5th centuries. Inside, the works of art and the frescoes are of remarkable beauty. Great artists worked here, above all the Genoese Baroque master Giovanni Battista Carlone and the French sculptor Pierre Puget, author of the splendid Altare Maggiore.
A curiosity: San Siro no longer has its bell tower. It was demolished in the early 1900s due to structural problems and never rebuilt.