Rivendell (Sindarin: Imladris) is a valley in J. R. R. Tolkien's fictional world of Middle-earth, representing both a homely place of sanctuary and a magical Elvish otherworld.

Others have written that it resembles the Celtic Otherworld of Tír na nÓg; and that it physically recalls the valley of Lauterbrunnen in Switzerland where Tolkien had gone hiking in 1911.

Tolkien stated directly that "From Rivendell to the other side of the Misty Mountains, the journey ... including the glissade [of Bilbo and the Dwarves] down the slithering stones into the pine woods ... is based on my adventures in Switzerland in 1911".

[T 14][2] The medievalist Marjorie Burns writes that Bilbo's approach to Rivendell parallels the early fantasy writer and translator of Norse legend William Morris's approach through the wilds of Iceland to a place he called "Water-dale" (Vatnsdale); both ride across uplands dotted with patches of green, becoming extremely tired; both then cross narrow ravines, and bogs; and both arrive at a hidden valley that offers shelter and comfort.

She compares the military-industrial complex with Mordor, and suggests that they yearned for a place of peace, just as Frodo Baggins felt an "overwhelming longing to rest and remain at peace… in Rivendell".

First comes the steep descent ...; pines are replaced by beech and oak; the air grows warmer; the first of the elves greet them with laughter and song, and then comes the inevitable water crossing that divides the rest of Middle-earth from the inner core of every Elven realm.

[6]Burns notes that both "Riven" and "dell" suggest a low place into which one must descend; and that a descent is characteristic of Celtic tales of entry into the underground realm of the Tuatha Dé Danann, whose chiefs each rule a burial mound.

[8] The Tolkien scholar Verlyn Flieger writes that both Frodo and Aragorn receive their renewed magic swords in Rivendell, marking them out as heroes in the epic tradition of Sigurd and Arthur, at the start of their quest.

"[12] Rebecca Ankeny comments that Tolkien uses verse, too, to signal the horror of the Elves when Gandalf speaks the dark lord's rhyme of the Rings aloud, in the Black Speech, threatening the end of Rivendell.

[13] The Tolkien scholar Gergely Nagy notes that Tolkien wanted to present the complex set of writings of The Silmarillion as a seemingly-genuine collection of tales and myths within the frame of his fictional Middle-earth; he modified The Lord of the Rings to ascribe the documents to Bilbo, supposedly written in the years he spent in Rivendell, and preserved in the fictitious Red Book of Westmarch, its name alluding to the Red Book of Hergest.

[16] In Peter Jackson's 2001 film The Fellowship of the Ring, Rivendell was represented by Kaitoke Regional Park, New Zealand, though the waterfalls were added with computer-generated imagery.