If you’re visiting Rome in the summertime, make sure you pack the right clothes – for weather and for “blending” in!  So, what do Italians wear when it’s hot?  The answer is not surprising – pants, shorts and cool shirts (like t-shirts and tanks).  In any case, you are a tourist and everybody will know it, and in many places the tourists will outnumber the residents. Even Italians dress a lot more casually when they're on holiday than they do when they're going to work.

During the winter, temperatures can get close to freezing, so sweaters and coats are necessary.  A heavy sweater and a water resistant jacket with hood should be fine for all circumstances.  It rarely snows in Rome, so boots are limited to those of the fashionable variety.

For footwear, remember that Rome has some tough streets to walk on – cobblestones, for example. Even the paved streets are uneven and have potholes to dodge. To make sure you can get around easily, wear comfortable, low heeled shoes. Tennis shoes or sneakers are probably the best for your feet. Open toed sandals may become troublesome if you are walking in a gritty or dusty area, like Ostia Antica.  During the rainy season (November through February or March), rubber-soled shoes will make those cobblestone significantly less slippery. It's best not to buy new shoes for the trip, because they may not be as comfortable after two hours on cobblestones as they were in the shoe store. Wear trusted, comfortable, well broken in shoes.

When visiting religious sites remember to cover your shoulders and knees. Long shorts (below the knee) and capris are fine; short shorts and miniskirts are not permitted. Women often carry a scarf to put around their shoulders when entering a church. However, covering your head is not required. Sandals are also fine; many monks and nuns wear them. Men and boys should remember to remove hats when entering a church. 

Italians tend to dress more formally when dining out than Americans, but you don't need a dress or a jacket and tie unless you plan to go to very elegant restaurants. A polo shirt and slacks or skirt are fine in summer, and sweater and slacks are fine in winter.

** Note:  Some of the original information for this thread came from the following forum thread:  http://rome-hotels.tripadvisor.com/Sh...