I am renting a car and would like a coastal route from Barcelona to St jean de Luz, France. I would also like to know hotels and sites to see along the route.
Those two cities are on different coasts. St Jean de Luz is on the Atlantic; it's a beautiful city and has a good beach.
Check out Google Maps or Rome2Rio to map the route between the two cities.
If you Google map the directions, or even if you just look at a map, you will find that St. Jean de Luz, France is just over the border from San Sebastian in the north of Spain. You could do a coastal route, but you would have to go around the entire Iberian peninsula. That would be great fun if you have time. Going directly, it looks like it takes about 5+ hours to drive through Zaragoza and Pamplona using the fastest route. You are planning to return your car in Spain to avoid the expensive charges incurred when renting in one country and dropping the car off in another, right?