Friday the 15th will be Ferragosto in Italy. The national holiday is formally observed for the Assumption of the Virgin Mary (when she was taken up to heaven directly without dying, the only human to do so, according to Catholicism). But like so many things in Italy, the Christian phenomenon was superimposed upon a former pagan ritual of mid-August, the feriae Augusti- a holiday to honor the emperor Augustus, shown in the picture. Ferie is still the Italian word for vacation (along with vacanze).
Much of the pagan fun remains, with very little religiousness. Every single Italian who can does his or her best to be off work not only on the fifteenth every year, but the whole week of Ferragosto, and if possible, the weeks before and after. This is why I have never taken a vacation in Italy in this month-shops closed, overcrowding in resorts (especially seaside resorts), higher prices. You would do well to avoid August, too, unless your destination is very exclusive or very unusual.