So I've never played Curse of Strahd or anything in the Ravenloft campaign setting - but I'm working on my own campaign world and I was reading through some texts and found out about Domains of Dread. They definitely sound like a concept I'd want to implement, but I'm not quite sure I understand them.
From what I read, it looks like (in Ravenloft) there are a bunch of different "domains" that are all separate from one another, kind of like countries are separated?
Are Domains of Dread separate from the Prime Material Plane? How does one get there from the aforementioned plane? Is it even possible? If not, is it possible to "summon" the creature who owns the domain into your plane, thus bringing their domain with them?
I know that with worldbuilding, pretty much anything goes, but I just want to have a bit of a baseline to work from.