Also, upon closer inspection, that France map doesn't even show most of France. It just shows a small section of northern France which doesn't even include Paris. You can see the routes leading down to Paris in the south.
I can't believe I didn't immediately notice that. I knew the shape wasn't very France-like, but what actually tipped me off is that a large part of southern France is bordered by water whereas the territory in the map is landlocked in all but the northwest.