The World of Arth
In Arth, there are many interesting places. Some your PCs will only hear about, some your PCs will visit, and some might not come up at all in this game. I will try to come up with a decent organizational scheme for them in here.
The bulk of the mainland. Most adventures start here, and the majority of people live here. It is covered in the ruins of a long lost civilization, and people scrape by however they can. Rules by powerful nobles, who have little to no affiliation to one another.
Forest of the Winds
Reached by crossing a vast ocean, this region is relatively unknown and only recently discovered thanks to some old maps King Boland unearthed. He and his captains are the only ones who know its exact location, and they hope to find vast stores of new wealth.