Slaughter on the Angirith Shelf

The land of Angmar is one of the grimmest places in all of Middle-earth. It is not black and twisted like Mordor, but heartbreakingly cold and barren It consists of two plateaus, the Nan Angmar (S. "Iron-home Valley") and the Angirith Shelf, one on either side of the main spine of the Hithaeglir, connected by the Angirith (S. "Iron Pass"). The region was accessible from the North Downs by traveling through the Ram Dúath, a range of winding canyons in the south-west of Angmar as was done so by the Host of the West prior to the Siege of Carn Dûm.
While the siege was successful driving out The Witch-King for the time and dismantling the Realm of Angmar from its capital the cost was great. Known as the Massacre at Carn Dûm a large part of the casualties of this event stem from the Slaughter on the Angirith Shelf (also know as the Slaughter on the Angrisîl) in which nearly the entire army of the loyalists of Rhudaur and the majority of those sent by Cardolan where slain by the traitorous Hillmen and Rhudaurim along with the frenzied Trolls of the North.