Rivendell

Rivendell, Karningul, or Imladris, is the home of Elrond and is located on Middle-earth in the Lord of the Rings continuum. It is one of the regions of Arda most badly warped by Mary Sues. Although it is a house (admittedly, a rather large house), they will often refer to it as a "city" and call Elrond a "king".

Its name is commonly misspelled as "Rivendale" in various fanfics by people who have only seen the Movies. (Or worse, Riverdale, by Archie comics fans.)