Here's an illustrated version of "The Walling of Asgard" from Hurstwic Norse mythology. The Hurstwic Society's mission is to educate people about the history of the Viking Age.
Timeless Myth's account of the walling of Asgard begins with a detailed description of the Norse cosmology and provides hyperlinks for many of the characters and places involved in the story.
The first book of Snorri Sturluson's Prose Edda, the Gylfaginning, or Tricking of Gylfi, contains a question-and-answer game in which Gylfi's questions reveal the nature of the Norse cosmos. The story of the walling of Asgard is found in Chapter 42.
Here's an image of the first page of the Codex Upsaliensis, the 14th-century manuscript of the Prose Edda, from a page about the Early Scandinavian Philology department at Uppsala University.
Like it so much you want to own the book? The Penguin Classic's edition of the Prose Edda provides a modern, accessible translation by a professor of Icelandic and Old Norse studies at UCLA.
A classic among mythical anthologies, with great artwork.
Renowned young adult literature author Kevin Crossley-Holland tackles Norse mythology.
This artist puts six of Sleipnir's legs in front, and two in back. Hmm. we're not sure what to think of that.
This picture has Sleipnir with four legs in front and four legs in back. Is that how you picture him?
Chatterbox Audio Theater offers a radio play of "The Walling of Asgard."