In mythologies the Far North is often associated with the limit of the cosmos, the most distant place you can travel to. A paradoxical place, because there you reach the limit of this world, and the border of the next. So the cosmic levels tends to merge there, the North of the Earth being confused with the Celestial North (Pole Star, Dipper, etc...). Not to speak about the Underworld. Another paradox: this margin is also some kind of center (since you are close to the Cosmic Axis, which runs through the Pole Star). So cosmic images are common, like a mountain for the Axis, and four island for the four directions... In the Irish lore I was talking about there are effectively four island North of the world.
