What to do in Rome in septiembre

New Year's Day Tiber dive from Ponte Cavour — a swimmer leaps in dressed as Babbo Natale, a tradition kept unbroken since 1946.

Carnevale Romano in mid-February — horse parades, masks and pulcinelle along Via del Corso and Piazza del Popolo, reviving the papal tradition.

Run Rome The Marathon in mid-March — a 42 km route past the Colosseum, Castel Sant'Angelo and the Vatican, with 20,000 runners leaving from the Imperial Fora.

Easter on April 5 — Papal Mass at St. Peter's on Easter Sunday and the Urbi et Orbi blessing at noon from the central Loggia.

Internazionali BNL d'Italia May 6-17 at Foro Italico — ATP Masters 1000 and WTA 1000 on clay, the direct warm-up to Roland Garros.

Festa della Repubblica on June 2 — military parade down Via dei Fori Imperiali and the Frecce Tricolori jet display over the Altare della Patria.

Opera under the stars at the Baths of Caracalla — Teatro dell'Opera di Roma stages Aida, Tosca and ballet in the 3rd-century thermal ruins through August.

Notte di San Lorenzo on August 10 — the Perseid meteor shower watched from Pincio and the Janiculum, Romans wish on the saint's tears.

Festa del Cinema di Roma October 15-25 at Auditorium Parco della Musica — red carpet, international premieres and retrospectives in Sala Sinopoli.

Quietest stretch of the whole tourist season — Vatican, Colosseum and Galleria Borghese line-free, hotels at winter rates and mild 16°C highs.

Pope's Midnight Mass at St. Peter's at 7:30 pm — the basilica by candlelight and the Vatican nativity unveiled in the square on December 24.