Quote Originally Posted by EatYerGreens
@ Macsen Rufus

That thing with Sweden is interesting because, when its port is built, that faces into Skaggerack, not into the Baltic.

I'm not saying that the port needs to have been built. What I'm getting at is that the positions of ports are predefined, in the startpos files (I think) and those coordinates may have a secondary use, in defining the point of contact between the sea and the land, for the purposes of reconnaissance.
Interesting thread, I've always assumed that rival factions' fleets blocked your fleets from reconnoitering a province? If you find this not to be the case then it may be that counterspying agents or border forts could block it, though I'm not sure...

The port positions are located in the startpos file. The coordinates seem to determine as to which coastal waters a port or shipyard interacts with. The facing is purely cosmetic, it simply sets the port sprite (different facings) used on the campaign map.