In reply to GraMc:
Heading for Sete gives a lot of possibilities.
Ferry to San Sebastian then: Basque country > Ariege > Sete
Drive down via Clermont Ferrand: Cantal (Dent de la Rancune) > Gorges du Tarn/Jonte > Sete
Drive down Vallee du Rhone: Bourgogne > Ardeche or Dentelles or Verdon > Sete
Close to Sete there are St Guilhem le Desert and the Caroux which will be OK in June (although the Caroux isn't really sport and St Guilhem isn't really for mixed abilities!)