Udûn is a circular valley in Mordor between the Carach Angren and the Morannon, formed by a violent volcanic upheaval. The valley gradually rises in altitude from the level of the Anduin basin to the plateau of Gorgoroth. Udûn is a bleak place, without trees or beast. Caves in the steep walls and cliffs of the vale are home to small tribes of Orcs and Trolls.
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