As a Belgium citizen how about hiking on one of the WW1 walks to Ypres, Vimy Ridge or the Somme or further along the 'front line' to Verdun, to be there on November 11th?
Get a train to Caen and then hike a circular walk south on the GR36 through the Suisse Normandie area to Thurry Harcourt, then return from there to Caen on the GR36 Varient route. Takes 4 to 7 days, depending on your walking speed and how much time you want to hang around in one or more places.
To know your choices, for example all over France, I also suggest you go on
www.gr-infos.com, ALL of the French GR routes are displayed, in great detail. At the bottom of the main linear routes page there is a whole list of circular routes.