We will be on a cruise in 2019, which will have an 11-hour port day in Civitavecchia. We really want to visit Narni and possibly Rome/Vatican, too. Is this too ambitious? There will be 6 of us, at the minimum, 2 elderlies, 2 adults and 2 teenagers. We would prefer to take the public transportation but it seems like there isn't any directly from Civitavecchia to Narnia. Should we hire a car or van?