We are slow seniors and will be in Bordeaux and Bayonne for a week in Oct on our own any suggestion What to do and see
You're options are limitless. You might want to be a little more specific on your interests, and you'll likely get some replies. Are you into wine? You can spend the entire week in the Bordeaux Appellation. The Dordogne has excellent cave art and castles to visit. As well as tiny villages to frequent (like the rest of France...) Carcassonne is too far away...
You can't go wrong in France.