Attestations
In chapter 13 of Völsunga saga, the hero Sigurðr is on his way to a wood when he meets a long-bearded old man he had never seen before. Sigurd tells the old man that he is going to choose a horse, and asks the old man to come with him to help him decide. The old man says that they should drive the horses down to the river Busiltjörn. The two drive the horses down into the deeps of Busiltjörn, and all of the horses swim back to land but a large, young, and handsome gray horse that no one had ever mounted. The grey-bearded old man says that the horse is from "Sleipnir's kin" and that "he must be nourished heedfully, for it will be the best of all horses". The old man vanishes. Sigurd names the horse Grani, and the narrative adds that the old man was none other than Odin.
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