I am currently running The curse of Strahd and plan to extend the adventure beyond the end of the published material. The party has not gone yet in a few places and I do not expect them to go there before the end of the adventure, but otherwise, I do not want us to pass again by the same places; I wanted to add new domains and additional content.
Looking at Barovie's map on p. 35, I can see that the left and right edges of the map are probably the edges of Barovia, since the right edge is marked A, which is the place where the party arrives for the first time after crossing the fog (which, in my opinion, means back in this direction simply leads them to get lost and spit back onto the map, as shown in "Mists of Ravenloft", pp. 23-24), and the left edge is probably more of that fog , given the description given in Chapter 14: Yester Hill (p.200):
Any creature that enters the deadly fog is subject to its effects (see "Ravenloft Mists" section in Chapter 2).
This is the reasoning I use to conclude that the left and right edges of the map are actually the edges of Barovie itself and that there is nothing left in either direction (though, if I wrong in this conclusion, I will be happy to answer this question in an answer).
My question is about the top and bottom edges of the map. At the top of the map are Mount Baratok and the various locations marked M. The bottom of the map is Mount Ghakis and a road that leads south to Amber Temple (though it may simply overflow from Barovia as A and the road to the west of Krezk, but there could to be a road to go elsewhere to Barovia). Nothing in this adventure implies that it is the edges of Barovia (yes, there is "fog effect" around the edges of the map, but I guess it's just for the style, otherwise Barovia is a clean rectangle – improbable).
Of course, as a deputy minister, I could simply decide that these are not Barovie's limits, because that suits my purpose, and if it turns out are what I will probably do, but I wanted to know if anything has been published on Barovia (probably from older editions of D & D, but there is something that I have missed in 5th, I would rather) who describe what could be beyond the edges of the map. Are there maps of previous editions that roughly correspond to the map I use, which shows everything north and south, or all that I missed in 5th The curse of Strahd?
Another way to ask: "Is Barovia the same size as the map, or is Barovia bigger than the map? "Also note that I'm interested in Barovia as a demiplan, the area of dread, do not everything related to what was at the time was likely a place in the material plane before Strahd and the Dark Powers occurred.