May is one of the best months to visit Rome, before summer heat and crowds descend on the city. It's not one of the city's busiest months in terms of festivals and special events, but there are a few fun and important happenings taking place.
Here are the festivals and events that happen each May in Rome. Note that May 1, Labor Day, is a national holiday, so many businesses, including most museums and some restaurants, will be closed.
May 1 - Primo Maggio
Primo Maggio is Italy's labor day and is a national holiday, so many Romans either head out of town or stick around for the huge concert in Piazza San Giovanni, usually starting in the early afternoon and continuing until around midnight. There are often protest rallies as well which may cause local transportation disruptions. Most sites and museums are closed but you can still walk on Via Appia Antica where a couple of the catacombs are usually open or visit the ancient Roman site of Ostia Antica, a short distance from Rome. Of course, open-air sites like Piazza Navona and the Trevi Fountain are always open.
First or Second Weekend of May - Open House Roma
Open House Roma happens just one weekend a year, during which public and private buildings in Rome, many normally off-limits to tourists, are opened for free, guided tours. Sites include a mix of the ancient to the Neoclassical, as well as Fascist-era buildings and some surprisingly bold, modern architecture. Reservations are required through Open House Roma.
Early- to Mid-May - Italian Open Tennis Tournament
Rome hosts the Internazionali BNL d'Italia, also known as the Italian Open, each May at the tennis courts at Stadio Olimpico. This nine-day, clay court event is the largest tennis tournament to precede the French Open, so many major tennis stars use the Italian Open as a warm-up. Top names in tennis appear here, including (in 2018) Venus Williams, Maria Sharapova, Francesca Schiavone (always an Italian fan-favorite), as well as Rafael Nadal (the 2018 men's winner) and Novak Djokovic.
Rose Petal Ceremony at the Pantheon (when Easter falls in March)
The Christian celebration of Pentecost takes place seven weeks after Easter Sunday — so when Easter falls in March, the Pentecost is observed in May. At the Pantheon, the Pentecost mass takes place at 10:30 a.m., and concludes with firefighters on the roof of the Pantheon dropping thousands of red rose petals from the oculus onto the floor below. It's a spectacular sight and understandably, it's tough to get inside the doors of the Pantheon that day. If you wish to be present for the petal drop, plan to arrive several hours early and prepare to wait.
Late May - Roma Summer Fest
This program of mostly rock music, with some jazz, world music and children's events thrown in as well, takes place at the Auditorium Parco della Musica, north of Piazza del Popolo and reachable by bus or tram. Prior to the Summer Fest, the Auditorium has a full calendar in May, with diverse acts from around the world and of virtually every genre.
There's a lot to do in Rome in June, too.