• The first level: Asgard, world of the Aesir; Vanaheim, land of the Vanir; and Alfheim, land of the light elves.
• The second level: Midgard, Land of humans (middle world/garden); Nidavellir, Land of the dwarfs; Jotunheim, Land of the giants (Jotuns); and Svartalfheim, Land of the dark elves.
• The third level: Hel, Realm of the dead; and Niflheim, World of the dead.

If Hel and Niflheim comprised one world, as is suggested in some sources, the ninth may have been Muspelheim (Muspell), the land of the fire giants. This region had no place in the tricentric structure of the universe, and Snorri Sturluson wrote that is was the first world to exist and that is lies in the southern hemisphere. Also, the worlds of Svartalfheim and Nidavellir may have been the same. No valid distinction can be drawn between the dwarfs and dark elves; they appear to have been interchangeable.

Bifrost was made of three colors with magic and great skill by the Aesir and is incredibly strong. It is also called Asbru, referring to its makers. At the end of the cosmos, this rainbow-bridge will collapse.

This cold, dark and misty abode of the dead is located in the world of Niflheim, on the lowest level of the Norse universe. No one can ever leave this place, because of the impassable river Gjoll that flows from the spring Hvergelmir and encircles Helheim.

Once they enter Helheim, not even the gods can leave. Those who die of old age or disease, and those not killed in battle, go to Helheim while those who die bravely on the battlefield go to Valhalla.

The entrance to Helheim is guarded by Garm, a monstrous hound, and Modgud. The giant Hraesvelg (“corpse eater”) sits at the edge of the world, overlooking Helheim. In the form of an eagle with flapping wings he makes the wind blow.

The realm of death, Helheim is part of the vast, cold region. Niflheim lies underneath the third root of Yggdrasil, close to the spring Hvergelmir (“roaring cauldron”).

Also situated on this level is Nastrond, the Shore of Corpses, where the serpent Nidhogg eats corpses and gnaws on the roots of Yggdrasil.

After Ragnarok, there will be a hall here for the punishment of murderers, oath breakers, and philanderers.

Midgard (“middle world”) is on the same level as Nidavellir (land of the dwarfs), Svartalfheim (land of the dark elves/dwarfs) and Jotunheim (the land of the giants).

It is located on the highest level of the Norse universe. Also found on this level are the worlds of Asgard and Vanaheim.

Alfheim is the palace of the god Freyr and the homeland of the elves of light.

Neither the elves of light nor the elves of darkness, who live in Svartalfheim, participate in any of the events described in the Norse myths. Elves do, however, have active roles in the literature of quite a few of the other branches of Indo-European mythology.

Jotunheim is ruled by Thrym (“uproar”), the feared king of the frost giants. The stronghold of Utgard, the chief city of Jotunheim and the abode of the giants, is ruled by the giant Utgard-Loki. Other strongholds include Gastropnir, home of the giantess Menglad, and Thrymheim (“house of uproar”), mountain stronghold of the giant Thiazi.

Beneath the three roots the realms of Asgard, Jotunheim, and Niflheim are located.

Three wells lie at its base: the Well of Wisdom (Mímisbrunnr), guarded by Mimir; the Well of Fate (Urdarbrunnr), guarded by the Norns; and the Hvergelmir (Roaring Kettle), the source of many rivers.

Four deer run across the branches of the tree and eat the buds; they represent the four winds. There are other inhabitants of the tree, such as the squirrel Ratatosk (“swift teeth”), a notorious gossip, and Vidofnir (“tree snake”), the golden cock that perches on the topmost bough. The roots are gnawed upon by Nidhogg and other serpents.

On the day of Ragnarok, the fire giant Surt will set the tree on fire.

Asgard was divided into 12 or more realms in which each principal god had his own luxurious mansion of gold or silver. The most important palace was Valhalla, the home of Odin, the chief of the gods.

Asgard, in Norse mythology, is one of the nine worlds and the homeland of the Aesir, the race of warrior gods. Located on the highest level of the Norse universe, it is surrounded by a high wall of closely fitted stone block

The walls surrounding Asgard were built by Blast (or Hrimthurs), who asked in payment the hand of Freya plus the sun and the moon. Odin agreed providing the walls be complete in six months. Hrimthurs had a magic horse, named Svadilfari, who helped him in his work. To Odin’s (and the other gods, especially Freya’s) horror, with but a few days left, Blast was almost finished. Loki, the trickster, turned himself into a mare and beguiled the stallion Svadilfari away. The job was not completed in time and no payment was given.

Also found on this level are the worlds of Alfheim and Vanaheim as well as Valhalla, an immense hall where warriors slain in battle await the final conflict.

In the middle of Asgard lies the plain of Idavoll (or Ida) where the Aesir meet to decide important issues. There the gods assemble in the hall of Gladsheim and the goddesses in the hall of Vingolf.

The gods also meet daily at the Well of Urd, beneath the Asgard root of the ash tree Yggdrasil.