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Niflheim is one of the Nine Worlds, more specifically the primordial world of ice and frost. It was one of the first two worlds in existence, alongside Muspellheim. It is also known as the World of Dark Mist, and is the land from which eleven poisonous rivers run.


Niflheim is known as the land of ice and mist. It is barren and cold, with the highest temperature in the warm regions being 40 degrees below freezing. It is primarily made of ice, although there are black mountains which can host fortresses, like Skadi's.

Niflheim has a gigantic spring at its center, known as Hvergelmir. This pool is the mother of all rivers and springs, and is the source of eleven poisonous rivers that run through Niflheim. Hvergelmir is located directly underneath the third root of Yggdrasil, and is inhabited by Nidhogg, the great dragon that gnaws at the World Tree and trades insults with the eagle that lives at the top.



Niflheim existed for all of eternity, along with Ginnungagap and Muspellheim. Eventually, its borders were melted by Muspellheim, the world of fire, causing a being known as Ymir to emerge from the ice, along with a cosmic cow known as Audhumla. Later on, Audhumla licked another being from Niflheim's ice, this being the ancestor of the gods, Buri. After the creation of Yggdrasil, the World Tree, Niflheim was attached to it.

Schism with Helheim

When Loki's three monstrous children were brought to Odin, he declared that Hel, one of the children, would rule over the dishonorable dead. He cast her into Niflheim, which eventually split so that part of it was her world, known as Helheim.

Magnus Chase and the Gods of Asgard

The Sword of Summer

Niflheim is seen out the window of the lounge when Magnus has breakfast on his first morning in Valhalla.

The Ship of the Dead

Magnus, Blitz, Hearth, Sam, T.J., Halfborn, Mallory and Alex go to the world of ice to stop Naglfar from launching and starting Ragnarok. They arrive in Niflheim overnight, and have trouble traversing through its icy waters. Using Jack to cut up the ice floe ahead, they travel on, getting colder and colder by the second. Eventually, they have to abandon ship and trek across the ice. They barely make it to Skadi's fortress, where they are saved by the giantess. In the morning, Skadi sends them to Naglfar

9 from the Nine Worlds

So's Your Face!

After arguing with Halfborn Gunderson, Mallory Keen accidentally enters Niflheim and becomes stranded. She makes her way to one of the eleven poisonous rivers, which lead to Hvergelmir, where Nidhogg is gnawing at the roots of Yggdrasil. Mallory offers him lessons in how to insult the eagle that lives at the top of the World Tree. After the lessons, Nidhogg allows Mallory to climb the world tree, and she makes it back to Valhalla.


  • If locations have Greco-Roman equivalents, Niflheim could be compared to Hyperborea, being lands of Frost Giants in perpetual sunshine.
  • Niflheim translates to World of Mist or Home of Mist.
  • It is explained in Ship of the Dead that Jotunheim and Niflheim have a close connection, both being realms of extreme cold and inhospitality. Therefore, it is easy to travel between them.
  • Niflheim is often interchanged and confused with Helheim.
Locations (MC)
Nine Worlds: Alfheim | Asgard | Helheim | Jotunheim | Midgard | Muspellheim | Nidavellir | Niflheim | Vanaheim
Cities and Towns: Boston | Flåm | New London | Provincetown | York
Administrative Divisions: Connecticut | Massachusetts | New Hampshire | North Yorkshire | Sogn og Fjordane | South Carolina
Countries: Confederate States of America | Norway | United Kingdom (England) | United States of America
Continents: Europe | North America
Other Locations: Alderman Estate | Bifrost | Blitzen’s Best | Boston Public Library | Bridal Veil Falls | Cape Cod | Charles River | Charleston Harbor | Chase Mansion | Dorchester | Fadlan’s Falafel | Folkvanger | Fort Wagner | Ginnungagap | Hotel Valhalla | Loki’s Cavern | Longfellow Bridge | Lyngvi | Morris Island | Nabbi's Tavern | Provincetown Airport | River Oure | Sessrumnir | Svartalfheim | The Thinking Cup | Yggdrasil