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 blocks. 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.