barcelona-marseilles

What 'bout a fast train from Barcelona to say Montpellier and then there you rent a car? There are four fast trains each day on that route and cost is ~80€ and travel time around 3h. (www.renfe.com)

From Montpellier, besides renting a car, you have the option to go to Marseille by train too, either a direct intercité (~2h, on 2nd class should be 13 to 27€, depending on the ticket) or a combination of local slower trains (www.sncf.fr).

You may find better prices if you look around... I just had a quick peek. But note prices vary wildly from one week to the next as festivites, local events etc have a great influence on prices -much like the airline industry.

But again, this prevents you from enjoying the "in between" (Costa Brava in Catalonia, and Côte Vermeille and Côte Bleue in France), so an alternative could be renting a car in Barcelona, dropping it in Port Bou -after having wondered the small towns of Costa Brava of course!- then a short hop to France by train and then you rent another car there. The most important thing is to avoid trans-border drop-off charges, which is what makes the price ridiculous.

I'd advise taking the train from Barcelona to Perpignan. According to the Auto Europe website, you can get compact rental for $134 trough Europcar, picking it up in Perpignan and dropping in Marseille for 10/13-19. Same price for dropping in Avignon.

In Rick's guidebook, he recommends Cucugnan, a tiny village in the Cathar region, as a great "back door" stop. My friend and I loved it. The Logis Auberge du Vigneron is a great little hotel with a superb kitchen. Don't miss the excellent cassoulet! And go to the operating windmill that's used to grind the flour used by the bakery in its base - great cookies.

On the way to MRS you might also want to drive through the Camargue to check out the black cattle, white horses and pink flamingos on the edge of the Mediterranean. In Marseille, enjoy walking around Vieux Port and take a boat around Chateau d'If and view the calanques. Then stop in to Chez Vincent Le Vesuve at 25 Rue Glandeves a short walk from the port. Best Pizza in France and all the food is teriffic. (Get there early or make reservations.) There are some great restaurants on the west side of the harbor. Because of the ethnic diversity in Marseille, you'll find it here in the food as well.

You don't need a car for any of this.
13/10. To Girona (2)
14/10. Cadaques day trip
15/10. To Narbonne (2)
16/10. Carcassonne day trip
17/10. To Nimes (2)
18/10. Arles day trip
19/10. To Marseille via Avignon

Yep David, that's indeed another very valid approach, and this way she doesn't need a car at all.

I will second David's suggestions.

We're recently back home after 6 months in Marseille, and I'll add the following:
--if you're going to Nimes, you should consider checking out Pont du Gard as well. It's the aqueduct that carried water to Nimes, and it's one of the few things that still impressed our daughter after visiting several ancient sites
--give yourself time in Marseille to check out Vieux Port and the Panier district. We also highly recommend a hike in the calanques, provided you're reasonably fit and are confident on trails. You can get to the trail head using public transportation (about a half an hour), and the views are spectacular.

If you got to Marseille earlier, you could rent a car and head up to the Gorges du Verdon. Again, the scenery is spectacular, though some of the roads are narrow.