Traveling by train from Barcelona to Arles in October. Want to jump to Salvador Dali Museum on the way for 1/2 day. Thought this might be better than a day trip (roundrip) from Barcelona. Is this possible or are there some suggestions? Planning on leaving Barcelona by early - mid-morning. Are there better trains than others to take? Any other advice about the trains from Barcelona to Arles (changing trains at border etc.)?
You will have to change at the border unless you take one of two trains, one morning and one evening, that run through with gauge-changing carriages. Have your passport easily available as you may be asked for it at the border or on the train, despite the Schengen agreement. I think the journey will probably be a bit too long to take a break at Figueres unless you are willing to leave very early or arrive very late, or spend the night there. I also don't know whether the station at Figueres has left-luggage facilities - museums often have cloakrooms but they usually don't take very large suitcases.