InNorse mythology,Ífingr (sometimes anglicised as "Ifing") is a river that separatesAsgard, the realm of theÆsir, fromJötunheimr, the land ofjötnar, according to stanza 16 of the poemVafþrúðnismál from thePoetic Edda:
Ifing the river is called, which divides the earth
between the sons of giants and the gods;
freely it will flow through all time,
ice never forms on the river.
— Larrington trans.
John Lindow inNorse Mythology (2001) states in reference to Ifing that a river on which ice will never form is one that runs swiftly and therefore is extremely difficult to ford (thus forming an effective barrier between the worlds of gods and jötnar).