Naples Cathedral (Duomo di San Gennaro)

The cathedral of Naples, dedicated to the Assumption but known to everyone as the Duomo of San Gennaro, is the religious heart of the city. It was commissioned by Charles I of Anjou, continued under Charles II and completed in the early 14th century under Robert of Anjou, on top of two earlier Christian basilicas. The neo-Gothic facade on Via Duomo is a late 19th-century reworking by Enrico Alvino, but it keeps a 15th-century portal with sculpture by Tino da Camaino.

Inside, the great draw is the Royal Chapel of the Treasure of San Gennaro, built to house the relics of the city's patron saint. It is a rich baroque space with frescoes by Domenichino and Giovanni Lanfranco, altarpieces by Domenichino, Massimo Stanzione and Jusepe de Ribera, a high altar by Francesco Solimena and a bronze gate by Cosimo Fanzago. The saint's blood is kept here in a phial and is displayed three times a year, on the first Saturday in May, on 19 September and on 16 December, when crowds gather to see whether it liquefies. Elsewhere in the church look for Perugino's Assumption, canvases by Luca Giordano, the Renaissance crypt by Tommaso Malvito and the 14th-century frescoes of the Minutolo Chapel.

From the left aisle you can enter Santa Restituta, the older basilica that predates the Gothic cathedral, and the early Christian baptistery, decorated with 4th-century mosaics. Beneath Santa Restituta, excavations have revealed Greek and Roman remains, including a stretch of Greek road and parts of a Roman aqueduct.

The Museum of the Treasure of San Gennaro, next door at Via Duomo 149, displays treasures from the chapel's sacristies and opens daily from 9.00 to 17.00. As a working cathedral, the Duomo closes to sightseers during services, so dress modestly and avoid wandering around during Mass. On the festival days the church is very crowded from early morning.

Allow an hour for the cathedral and its annexes, and another hour for the treasure museum. The Duomo lies at the eastern edge of the historic centre, a few minutes' walk from Via dei Tribunali and Pio Monte della Misericordia, which holds Caravaggio's Seven Works of Mercy. Duomo station on metro Line 1 is the nearest stop.