Do Heidelberg and Strasbourg have left-luggage lockers for day-use? Same question for Caen and Bayeux.
According to the SNCF Gares-en-mouvement site, Strasbourg has left luggage facilities but Caen and Bayeux do not.
If I have translated the German correctly on the German Rail site, Heidelberg has left luggage facilities.
According to the Heidelberg station layout on my website, there are lockers (symbol of suitcase with a key over it) in the "bridge" over the tracks in the Heidelberg Bahnhof.