The hills of Emyn Muil, upon either side of Nen Hithoel, was a vast, seemingly impenetrable maze of rocky crags in the region of Rhovanion in Middle-earth. The Emyn Muil lies between the eastern part of Rohan and the relatively empty lands that contained the Dead Marshes and the Nindalf (Wetwang). It was approximately seventy-five miles from east to west and some one-hundred miles from north to south.