Primordial cold, mist, and ice; in the north at the time before time. Hvergelmir is situated here.

Niflheimr, 'the home of mist' or 'the home of darkness,' is the primordial cold and dark region in the north that existed before the creation of the world. From Niflheimr flows Hvergelmir, the cold spring from which eleven rivers, the so-called Élivágar, have their origin. These rivers carried poisonous icy water into Ginnungagap, the primordial void, and created the conditions for the emergence of life when they met the heat from Muspelheimr in the south.

Hvergelmir is described in Grímnismál 26 as the spring from which all rivers on earth's surface originate, and beneath Yggdrasil in Niflheimr Níðhöggr and countless serpents gnaw at the root. This association makes Niflheimr one of the three roots' terminal destinations and ties the cosmological dimension to the eschatological.

In Gylfaginning, Snorri states that Hel, the realm of the dead, is located in Niflheimr, specifically the part called Niflhel. This is one of mythology's most important boundaries: Niflheimr as a cosmogonic force and Niflhel as the abode of death often overlap in the sources, though Snorri's systematization places them vertically beneath Midgard.

The Élivágar are named in Vafþrúðnismál 31 as the primordial rivers from which creation arose, a reference that underscores that Niflheimr is the source of frost and ice. The rime and cold from Niflheimr constitute one of the two primordial forces that made creation possible, as much creative as destructive.

Sources in the Eddas

Vafþrúðnismál 31
The Élivágar are named as the origin of frost and ice in Niflheimr.
Grímnismál 26
Hvergelmir as the source spring of all rivers; Níðhöggr gnaws at Yggdrasil's root.
Völuspá 38-39
Niflhel and the dead who dwell there are described in connection with Ragnarök.
Hávamál 96
Reference to the cold north's cosmological dimension.

Interpretive traditions

A What we know

Niflheimr is the primordial ice-cold region in the north from which the Élivágar flow.

Hvergelmir in Niflheimr is the origin point of all rivers and the abode of Níðhöggr.

Niflhel is the death-realm portion of Niflheimr, located beneath the other worlds.

B What we think we know

Whether Niflheimr and Hel/Niflhel were originally identical places or are distinctly separated in older tradition is debated.

The Élivágar, named in Vafþrúðnismál, are unidentifiable with real rivers, and their exact number and names vary across sources.

C What we do not know

Niflheimr's exact cosmological position relative to Yggdrasil's roots and the other nine worlds is not unambiguously fixed in the sources.

Whether Niflheimr was conceived as one of the nine worlds or as a pre-cosmic realm outside the created order is unclear.