FCO to Civit. Port

Common question. See RoninRome.com for detail directions for using the train. Of you have to define best. For me, best is a car and driver door to door. But most use the train.

By train it's 1h22min to 1h50min (one train change, likely at Roma Trastevere station). Cost is 11 Euro per person one way. However you will likely need a taxi from Civitavecchia train station to the port (just over 1/2 mile, but with luggage it's a long walk) By Private car transfer it's 45 min drive from FCO to CIV. Cost is 120 euro and up (for up to 3 passengers) What is best I'll leave it to you. If you have a lot of luggage and you have 3 people traveling together, the private transfer, albeit expensive, could be an easier and more comfortable option.

Would you buy train tickets before or at the airport?

Jason, very easy to buy your tickets at the train station at Terminal 3 of FCO. Since you will most likely be on Regionale trains, you can't buy the tickets online more than 7 days out from the time of travel. You can see the schedules - you just can't buy the tickets.

There are actually two routes. Most people simply take the Leonard Express into Termini and the train directly to Civit. It would be a little cheaper and probably faster to take the local train from the airport (not the Leonard Express) to the Trastevere station (Think it is the station just prior to Termini) and then change tracks and catch the local train to Civit.. In some ways it is an easier transfer at Trastevere but not as obvious. Once at the station, you probably have walk. Most people do. It is an easy flat walk along the beach. Just follow the flow. Lots of people doing it. Taxis are available but a big fare for a half mile ride. A public bus is available is for 1.1E (last year, probably a little bit higher this year) but the line will be long and you can walk faster. Once at the port entrance a dedicated shuttle bus will take you to your ship's check in point. Can be a real zoo at this point if more than one ship in port.