Mount Rerir

The lands westward of the Blue Mountains were largely consumed by the Sea in the aftermath of the War of Wrath, but the mountains themselves survived. Mount Rerir stood out to the west of the range, but whether it survived the cataclysm or not is unclear. Maps of this region from the Third Age show highlands where Rerir once stood, but no single peak is shown or labelled. The implication is that Rerir was greatly reduced during the final War of the First Age, but probably not entirely overwhelmed.

The name Rerir is not explained, and does not appear to have any obvious Elvish derivation. It is perhaps derived from the name of the character Rerir in the Völsunga saga. If so it this is a unique etymology among the place-names in the Silmarillion, though the use of sources like this was not unknown to Tolkien. Many of the names of Dwarves in the Third Age, as well as the name 'Gandalf', come from the Poetic Edda, the same source as the Völsunga saga.