Rome is best visited April through June and September through October. Spring brings mild weather (16C to 24C), Easter celebrations in the Vatican and the Colosseum area, and the Rome Marathon in March. The azalea display on the Spanish Steps in April is one of the city's most beautiful seasonal moments. September and October have excellent weather, 20C to 26C, with summer heat fading and the late harvest events in the Castelli Romani hills south of the city. July and August are extremely crowded and very hot, regularly 32C to 36C. The Vatican and Colosseum lines require advance booking months ahead. August sees many Romans leave the city but tourist sites remain packed. Ferragosto (August 15) is a national holiday when most local restaurants and small shops close. December and January are the quietest months. Mild winters, 8C to 12C, make sightseeing comfortable with far fewer visitors. Christmas in Rome brings nativity displays in the churches and candlelit evening masses at Santa Maria Maggiore and Santa Croce.