The ridge upon which the companions stood went down steeply before their feet. Below it twenty fathoms or more, there was a wide and rugged shelf which ended suddenly in the brink of a sheer cliff: the East Wall of Rohan. So ended the Emyn Muil, and the green plains of the Rohirrim stretched away before them to the edge of sight.
- The Two Towers (Book 3), Chapter 2
The East Wall of Rohan is a sheer cliff face which marks the western edge of the Emyn Muil as they meet the plains of the Eastemnet, as well as the north-eastern border of the kingdom of Rohan.