Hi Patrick,
so that means you follow the road from France and I think it will be the atalantic ocean side with Bordeaux?
this is not my region where I do my trips. But I have a Spanish friend overthere in Valadolid and one in the near of Madrid. Both are M109 Riders and I could ask for some challenges for you.
The "tunnel-roads" in the hills or the very smal canyons you can have on some places, but mostly in the north-side of the pyrenees in France (Roussillion to be precise).
Ok let me know if you are interested in some good streets in the northern Spain map. I know there is some very impressive road up in the peaks of Asturias. An I think it is the road with the most possible twisties in Spain. I will ask my spanish friends and get more information for you.
I wish you alle the best to enjoy your trip, which is so great - even for people like me, who living here in "Heaven". Take care, ride safe, save all the things on your build in harddrive to think of it in some years in the rocking chair.
On my homepage you will find some information about some of the trips and there is a english translation button on the left. Well - its google translation, but it is translation.
Roussillion