Festeron Bay is a cavity of the Flathead Ocean, and the eastern edge of the Festeron islands, known to be filled with both sharks and masses of intelligent seahorses. The Western Sea would be completely isolated from Festeron Bay if it were not for three rivers: two which divide both islands from the Antharia mainland on their north and south sides, as well as the Festeron River which divides the islands from one another.

SOURCE(S): Wishbringer, Wishbringer (novel)