Okay, Rome is great. But the cruise ship port is Civitavecchia which is quite a distance from Rome. Be prepared to sit in lots of traffic and probably encounter some striking group blocking the way is you take an excursion bus to Rome. The train is a little bit of a walk but more reliable and there is a pass at the tourist info center at the port for the train and Rome transit for easier navigation. On its own, Civitavecchia is a huge waste of time. There is a unique church with murals by Hasegawa. There are beaches, but, of course, Italy beaches are all rocks- bring shoes that can go in the water.