In the same way, why not keeping informations on provinces you once visited ? I.E. you had a scout in a province, but now he as moved elsewhere and you have no more info. It seems that you have forgotten the name of the province (there's a ???).
Why not having the name of the province and the infos you had last time you knew something about that province ? I.E. : 'last time you visited that province, there was 40 hostile independant units, mainly militias, that was 5 turns ago'. Or something like that
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