Patron saint and protector of Naples, San Gennaro is celebrated by hundreds of Napoletani. Expect singing, crying and praying as his statue majestically moves through the streets of town. The Feast of San Gennaro ends with the miracle of the liquefaction. Since the forces of divine providence don't necessarily follow the Gregorian calendar, the miracle of the liquefaction of the blood of San Gennaro might not fall precisely on the day of the procession, though it seems that quite often it does. The blood of the saint is contained in a vessel kept in the Duomo of Naples, and through the intervention of the saint the blood turns liquid again, to attest to the faithful that he still watches over the city.
fonte: destinations.hilton