Very minor: why is the shadow of the Emerrand fortress on the map?

[BattleLord]

This is something I noticed on my first playthrough too, but forgot to make a note of it.
It seems a bit strange that a map, which usually doesn't have any shadows on it at all, suddenly does have the shadow of this fortress on it.
At first when exploring, I thought it was some kind of weird marked area, until I opened up the map and noticed what it was.

 

[DavidBVal]

good point, actually all maps DO have shadows, but Emerrand is so big that it's noticeable.