Where to go and what to do in France

Hi, we are going back to France in September and wondered where to go and what to do. We have 5 weeks so have plenty of time, the last time we went to Brittany, Normandy, Paris and off course the Calais area, this time looking to go further South.  We are not interested in going round the vinyards, but we do like scenic places, nice towns, castles, rivers and lakes, we enjoy walking( not more than 5 miles) and we like cycling (easy scenic routes not main roads) we would welcome suggestions of places to visit and places to stay, we try to keep the cost down by using our ACSI discount card where possible and will be touring in our Bailey motorhome towing a small car. All suggestions welcome.