Niflheimr Sea

Located between the continents of Demia and Aeroh.
These bleak, icy northern waters are often turbulent and stormy, not to mention often engulfed in mist.
It is also the home of many dangerous creatures, both magical and mundane. For much of the year, the top portions of the water is frozen over.
It is a very difficult and dangerous crossing without the aid of magic or other supernatural abilities.
As such, few attempt to do so and Aeroh is isolated from much of the world, which suits its inhabitants just fine.