http://www.theguardian.com/books/2015/oct/23/jrr-tolkien-middle-earth-annotated-map-blackwells-lord-of-the-rings
Apparently this was one of the printed fold-out maps from an earlier edition which Tolkien made notes on for illustrator Pauline Baynes to make a big color poster of in 1970.
It has various jotted notes in pencil and green ink and is being offered by Blackwell's Rare Books for £60,000.