Radhrim (Raðrim) was a forested region in eastern Doriath, located between the rivers Aros and Celon. Although what appears to be the same region is also called Arthórien, it is unknown if these two regions were the same (or if one was situated within the other).
- J.R.R. Tolkien, Christopher Tolkien (ed.), The War of the Jewels, "Part Two. The Later Quenta Silmarillion: Of Beleriand its Realms (Chapter 11)", pp. 183, 189
- J.R.R. Tolkien, Christopher Tolkien (ed.), The Lost Road and Other Writings, Part Three: "The Etymologies", pp. 382-3 (entries RAD- and RĪ-)