Monza is a year-round city, but September is its most animated month: the Formula 1 Italian Grand Prix brings racing fans from across the world, fills every hotel in the area, and creates an electric atmosphere in both the park and the city. Book well in advance if you want to attend. The rest of the year Monza is a pleasant, quiet city — spring is particularly nice for the park, with the Rose Garden at its best in late May and June. Summer weekends bring crowds of Milanese to the park but the city centre stays relatively calm.