Train trip from Barcelona to Paris

Yes, it is possible.

Do you have the Rome to Rio app? It might give you some ideas for towns along the way. Or a guidebook? Or a map of the area?

Sort of... the normal "trip" from BCN to PAR is done by high-speed train these days, and it takes 6.30h. There is no other type of direct trains. HOWEVER, you could do 'stretches' of the itinerary also using high-speed trains. For example, from the top of my head, Barcelona-Girona-Beziers-Paris. Both Girona and Beziers are worthwhile spending time in.

There is a fast train service from Barcelona to Paris, and it takes 6.5 hours--650 miles. When we were on the train in June, it topped out at 185 mph just outside Paris. You could get online and find the cities that train stops at--and stay there.
Have you considered just taking it all the way at once?

The thing about the high-speed trains is that they make very few stops; that's one of the ways they can chew up the miles so fast. The easiest way to see the stops made along the usual routing from Barcelona to Paris is to go to the user-friendly Deutsche Bahn website.

• Use Barcelona Sants as the origin and PARIS as the destination.
  
• If you know the day of the week you plan to travel, pick a date a couple of weeks in the future that falls on the same day; if you don't know, it's not a big deal at this point, but I'd choose a weekday (going with the odds).
  
• Choose a morning departure time as a starting point.
• Click on one of the trains. Note the travel times and the number of transfers.
• Click on Show details. That will display the transfers, if any.
• Click on Show intermediate stops. Now you have a list of all the stations where that particular trains pauses.
  

The TGV departing at 9:25 AM makes the following stops: Girona, Figueres Vilafant, Perpignan, Narbonne, Beziers, Montpellier Saint-Roch and Nimes. Slower departures make a lot more stops. You are not limited to the places I've listed here. You could plan to take primarily that fast train but get off at one of the listed cities and switch to a slow train for the next segment if you wanted to stop over in a small town not served by the fast train.

I haven't been to Beziers or Nimes.

Girona is great--a medieval city still partially surrounded by a wall. There's a very good art museum plus two major churches. There's a big-deal flower festival in May.

The only reason I'd choose Figueres as a stopping point would be to go to the Dali Theatre-Museum; otherwise, I think you have more-interesting options.

Perpignan definitely has points of interest but isn't as in-your-face pretty as some other French cities. It's a good transportation hub for the local trains and buses fanning out to smaller towns in that part of France.

Narbonne is more prettified.

Montpellier is a sizable university city. There's an atmospheric historic district.

The 11:16 AM departure is much slower; it's a series of local trains with many stops (including Girona, Figueres, Perpignan and Narbonne, plus the popular small town of Collioure), then at Narbonne it veers through Carcassonne to Toulouse (a very handsome city with many pink-brick buildings) and ultimately Bordeaux, where you could get a fast TGV to Paris or continue on a slower train with more possible stops.

That should get you started. Of the places I've been, my first choice would be Girona. If you want to spend your extra time in Provence, Nimes would be a good stop.

Thank you everyone you have given me useful information.