Ered Engrin

The northern wall

The Ered Engrin were a long chain of mountains that Melkor raised across the north of Middle-earth in the Years of the Lamps, when he first set himself against the Valar and sought a fastness of his own. They ran from east to west along the cold regions of the world, and beneath them he delved his two great fortresses: Utumno far in the east, and Angband at their western end, nearer the sea, as a defence against any assault from Aman.

The mountains served Morgoth as a natural shield. When the Noldor laid siege to Angband, they could surround it on the south, west and east, but they could never pass the Iron Mountains to close the ring on the north, and Morgoth continued to send his spies and his creatures out through the far passes. Above the gates of Angband stood Thangorodrim, the highest peaks of the chain, which Morgoth raised out of the debris of his tunnelling.

The land south of the mountains, between them and the plain of Ard-galen, was the blasted country of Dor Daedeloth. The Ered Engrin also lay behind the northern part of Hithlum, and the bitter cold of that land was ascribed to their nearness.

Fate

The Iron Mountains were broken along with Angband in the War of Wrath, and their western reaches were drowned with Beleriand. Later ages remembered only their eastern remnants in the frozen north beyond the Grey Mountains, where dragons still bred in the Withered Heath.