Can't say much about the part before you hit the south coast, but it was very interesting getting off the motorway and driving across the French-Spanish border along the costal road (N-114 in France, N-260). Be warned, that the road winds along cliffs and can be very narrow, not for the faint of heart, but some breathtaking views across the sea. Once you are on it, you can't get off for about 50 miles.