Well, Antasia is a small-to-mid-size region/kingdom, bordered on all sides by hostile environments. To the north is the Nomansland, a downright freaky place. South is the Great Wastes, an uncharted desert, filled with all kinds of unfriendlies. To the west is the Poison Sea, which even the bravest pirates will not sail. And to the east, across the Sea of Maddil, is the Land of the d**ned, which people only speak of in whispers.
And I only placed the major landmarks and cities.