The Nordic Mysteries were given in nine chambers, or caverns, the candidate advancing through them in sequential order. These chambers of initiation represented the nine spheres into which the Drottars divided the universe:
(1) Asgard, the Heaven World of the Gods;
(2) Alf-heim, the World of the light and beautiful Elves, or Spirits;
(3) Nifl-heim, the World of Cold and Darkness, which is located in the North;
(4) Jotunheim, the World of the Giants, which is located in the East;
(5) Midgard, the Earth World of human beings, which is located in the midst, or middle place;
(6) Vana-heim, the World of the Vanes, which is located in the West;
(7) Muspells-heim, the World of Fire, which is located in the South;
8) Svart-alfa-heim, the World of the dark and treacherous Elves, which is under the earth;
(9) Hel-heim, the World of cold and the abode of the dead, which is located at the very lowest point of the universe.
It is to be understood that all of these worlds are invisible to the senses, except Midgard, the home of human creatures, but during the process of initiation the soul of the candidate—liberated from its earthly sheath by the secret power of the priests—wanders amidst the inhabitants of these various spheres. There is undoubtedly a relationship between the nine worlds of the Scandinavians and the nine spheres, or planes, through which initiates of the Eleusinian Mysteries passed in their ritual of regeneration.
source: The Secret Teaching of All Ages (1928)