Witcher 3 - Ocean West of Velen?

[JNK]

So I played alot Witcher 3 in the past month but there was always one thing that made no sense for me.

If you go straight to the west in Velen, a big sea/River will appear. On the Other side will still be terrestrial though. You can see it here:

You can see a new continent/island left in the picture.

 

But if i check the overall Witcher 3 Map like this:

 

Or this:

 

That landmass shouldnt exist at all. There should be a big ocean?

 

Is this a mistake made by the developer or didnt i got anything? What Island/Country should this be? it cant be skellige, scince thats FAR away. So which country is in west of Velen??