The 8th month is reputed dead in the city. Shops are closed, public transports are slowing down, italians are at the sea side, the metro to the beach is crowded... 2009 was the first year I was experiencing it in Rome. In my opinion it was fine, even though some of my usual shops were closed. I just felt the emptiness on the Ferragosto (Assumption) week-end. The building was empty. Even Italians that are not on holidays at that time (a small portion) leave the city to visit family or spend a long week-end at the sea or countryside. The only thing you should avoid just before Assumption day is to look for a sun lotion because you are supposed to go to the beach on the next day.... I did it, and had troubles to find what I wanted without spending the triple of the usual price in a pharmacy :D
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