I have been staying at a campsite on the west coast of France just north of Bordeaux for 20 years. Great site on sand in a pine forest. Short walk to beach with fantastic surf, cheap restaurants but no glitz and very few brits. Hourtin Plage is complete chillout. I have also stayed on a site south of Biarritz at St Jean de Luz. I remember watching people dig trenches around their tents and laughing.... until a storm hit in the middle of the night and my tent was washed away. The Pyrenees are very near! Have fun.