Unless you like trains and changing, I would look at another route.
There is no train from FCO to Civitavecchia. You have to go from FCO to Roma Termini and jump on another train to Civitavecchia.
We took a private van from FCO to Civitavecchia in 11.05. It cost 120 Euro including tip.
SS Norway (12 times) '85 - '97; Radiance OS 06/01; Island Princess 11/04, Grand Princess 11/04/05, Golden Princess 7/21/06, Golden Princess 2/24/07, Explorer of the Seas 12/23/07, Island Princess 11/15/08
Hi Jimmy 1 In regards to your enquiry about train to Cervviche(Rome), the round trip on the train between Rome and the port is only 11Euro's and I am sure there is transport from the airport to the train station in Rome called Roma Termini thus unless you are short of time it would be alot cheaper than a Van. We are doing the Port to Rome round trip in about 3 weeks. Good Luck Chargap