Roads & Campsites around Santander

Hi all

We are thinking of travelling to Santander next year spending a few days in Northern Spain and then travelling up to the Dordogne for the remainder of the trip. We have travelled through France many times before but this would be the first time in Spain and my questions are:

What are the roads like travelling from Santander to the French border, I appreciate that there are the motorways but we prefer to avoid them the majority of the time as you miss so much of the country that you are travelling through.

Can anyone recommend any good smallish sites around  Santander as we will arrive on the evening ferry and I would like to get pitched up reasonably soon after landing.

Many thanks for all contributions