The port for Rome is about an hour or so from the city. Take the train to Rome as it is much quicker than an excursion bus. The train station is a short walk from the port entrance. The round trip is 9 Euros and also includes use of the metro in Rome. Rome can easily be walked if you have a good map.
This city is very easy for one to walk around. We were there on Fat Tuesday and saw the Carnival parade. The costumes were beautiful. Buses and taxis are around for use if you prefer not to walk.
Stay near the water front. You can then take the metro into the main city if you wish. The aquarium was a must see. It is located near the cruse ship terminal. Be aware that there are some teenagers that may try to pick your pockets. Be safe and keep your eyes open for this.
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