The Cirith Ninniach was a narrow and rocky pass running through the Ered Lómin in the western part of the Beleriand. According to The Atlas of Middle-earth, the pass was some fifty miles in length from its beginnings in the coastal lands near the Great Sea to Gate of the Noldor. It was situated between the mountains that divided the lands of Hithlum and Dor-lómin, and served as the means of connecting Hithlum to the Firth of Drengist. A stream was here fed by a freshwater waterfall that ran through the tunnel leading to the Gate of the Ñoldor, as well as other smaller falls coming down from the sides of the mountain.