Niflheimr (Old Norse = 'the dark home') is one of The Nine Worlds.
It is situated in the icy north and it existed even before the creation of the world.
Niflheimr is separated from the fiery world Muspellsheimr by Ginnungagap.
One of the roots of Yggdrasill streches out towords Niflheimr and the spring Hvergelmir lies beneath it.
In Gylfaginning, Snorri identifies Niflheimr with Hel