Mount Rerir

In J. R. R. Tolkien's Middle-earth legendarium, Mount Rerir was a mountain in Thargelion (a region of Beleriand) to the north of Lake Helevorn and one the sources of Gelion.

The land around the mountain belonged to Caranthir, who built a fortress on its western slopes. The fortress was destroyed during Dagor Bragollach. Elven forces probably withdrew from the area after the battle, and most definitely after Nirnaeth Arnoediad.