Gná and Hófvarpnir
In Norse mythology, Gná is a goddess who runs errands in other worlds for the goddess Frigg and rides the flying, sea-treading horse Hófvarpnir (Old Norse "he who throws his hoofs about", "hoof-thrower" or "hoof kicker"). Gná and Hófvarpnir are attested in the Prose Edda, written in the 13th century by Snorri Sturluson. Scholarly theories have been proposed about Gná as a "goddess of fullness" and as potentially cognate to Fama from Roman mythology. Hófvarpnir and the eight-legged steed Sleipnir have been cited examples of transcendent horses in Norse mythology.
Attestations
In chapter 35 of the Prose Edda book Gylfaginning, the enthroned figure of High provides brief descriptions of 16 ásynjur. High lists Gná thirteenth, and says that Frigg sends her off to different worlds to run errands. High adds that Gná rides the horse Hófvarpnir, and that this horse has the ability to ride through the air and atop the sea. High continues that "once some Vanir saw her path as she rode through the air" and that an unnamed one of these Vanir says, in verse: