train travel italy to spain

Sometimes cheapest, best, shortest just do not go together. Best has no mean anyway since it some related to personal preference. Since you are so indefinite at both ends by hundreds of miles, my recommendation would be one of the budget airline as long as you can comply with all of their restrictions. The train ride would be long and probably more expensive.

We are not interested in flying. . .only traveling by rail. I understand there is a train from Civitavecchia near Rome to Barcelona. Is this correct?

Probably not. Civit... is the cruise port for Rome. It is possible that a train from Termini would pass through Civit on the way up the coast. Cheapest trains will be a combination of Regionals and/or ICs but that will make for a very long trip. You would not board a train in Civit.. to go to Barcelona/Madrid. And you need to make up your mind about leaving from Venice or Rome. They are not close or in line with each other. What does Best mean to you.

lin, I'm not sure it's going to be possible to meet all of the criteria you listed. A combination of "cheapest" and "shortest" is usually not possible. There isn't a huge difference in the shortest travel times from either Rome or Venice. IMO, the options from Rome appear to be slightly better. One of the shortest travel times I could find from Rome to Barcelona was a train departing at 16:00, arriving 10:28 the next morning (time 18H:28M, 1 change, reservations compulsory). As that's a night train, using a Sleeper or Couchette would be an additional cost. I couldn't find information on the price. Although you stated that you'd prefer not to travel by air, the alternative to a LONG rail trip would be a flight from Rome / CIA to Barcelona / BCN via RyanAir. The cost is as low as ~€30 and flight time 1.5 hours (which doesn't include check-in, security and the other usual airport times). There are other budget airlines operating from Rome / FCO. Good luck with your planning!

You were right in thinking of Civitavecchia as a starting point to Barcelona but not by train. Tink ferries! The only train you would need is Rome-Civitavecchia about one hour and 6/7 euros. You can walk from the station to the harbor, or take a 5-minute taxi ride. Then take an overnight ferry to Barcelona. Nice ships, choice of comfy chairs or cabins, restaurants, bars all cheaper and much easier than trains. Ferries leave late afternoon, arrive next afternoon in Barcelona. Timetable depends on which month you plan to travel.