Tol Withernon might have been inspired by the town of Withernsea in Yorkshire, where, not far from it, Tolkien was stationed during World War I. While the town of Withernsea isn't located on an island presently, a local tradition claims that at some point in history it actually was an island.
- J.R.R. Tolkien, "I-Lam na-Ngoldathon: The Grammar and Lexicon of the Gnomish Tongue", in Parma Eldalamberon XI (edited by Christopher Gilson, Arden R. Smith, and Patrick H. Wynne), p. 3
- John Garth, Tolkien and the Great War, "Part three: Tol Withernon and Fladweth Amrod", p. 236
- Paul Strack, "G. Tol Withernon (ar lim gardhin arthi)", Eldamo - An Elvish Lexicon (accessed 22 April 2022)
- John Garth, Tolkien and the Great War, "Part three: Tol Withernon and Fladweth Amrod", p. 234