Twilight of the Gods
Alfarheim is the home of the light-elves, poweful beings who are not as strong as the gods, but which mortals still see as divine, even offering sacrifices to them for fertility and good fortune. It is said to be a beautiful blue realm, ruled by the god Freyr and goddess Freyja though from a distance, as they themselves are hostages in Asgard.
The alfar – elves – in Midgard claim this realm as their ancient homeland.
Alfarheim is a Demi Plane connected to the Elemental Plane of Air. It is mildly good aligned and has lower gravity than the Prime Material.