This division causes that you can not directly sail, for instance, from The Skellige Isles to Novigrad. It is divided into few major areas - White Orchard, Velen and Novigrad, The Skellige Isles, Kaer Morhen and few more smaller ones like Royal Palace in Vizima or Isle of Mists.
The Witcher 3: Wild Hunt is not a single open world game. The Witcher 3: Wild Hunt tutorial takes place in Kaer Morhen, the stronghold of the witchers. Some basic facts about the game world and this atlas
