Lake Mithrim

Hithlum
J. R. R. Tolkien's legendarium location
Type	Cold, rainy, fertile region
Location	Northwest of Beleriand, between the Ered Wethrin and Ered Lómin
Lifespan	First Age
Founder	Noldor

In J. R. R. Tolkien's fictional universe of Middle-earth, Hithlum (IPA: [ˈhiθlum], archaically IPA: [ˈxiθlum]) is the region north of Beleriand near the Helcaraxë.

Hithlum was separated from Beleriand proper by the Ered Wethrin mountain chain, and was named after the sea mists which formed there at times: Hithlum is Sindarin for "Mist-shadow"; its Quenya counterpart is Hísilómë (IPA: [ˌhiːsiˈloːmɛ], archaically IPA: [ˌxiːθiˈloːmɛ]).

Hithlum was subdivided in Mithrim, where the High Kings of the Noldor had their halls, and Dor-lómin, which later became a fief of the House of Hador.

The Ered Wethrin ("Mountains of Shadow") formed the southern and eastern wall, and had only a few passes; as such they formed a natural defensive line. The western wall was formed by the Ered Lómin or "Echoing Mountains", which curved north-westward to the Helcaraxë.

The land of Lammoth lay west of the Ered Lómin and was not part of Beleriand or Hithlum. The land of Nevrast was separated from Hithlum by the southern part of the Ered Lómin range. Nevrast was usually seen as part of Hithlum, but its climate was that of Beleriand.

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