This hilly and mountainous area once checked the northward expansion of the Orchish Empire. The Gimhak controlled this area long before the arrival of the orcs and fought to keep it that way. For nearly twenty years, the orcs had to make circuitous routes around this rugged region to reach their northern settlements. The area was captured by the orcs in the Gimhak War.
There are thousands of caves in Bileddanul. These are inhabited by bugbears, kobolds, dragons, and numerous other hideous beasts. The caves are also haven for brigands and outlaws. Many creatures have escaped their pursuers by entering these caves and the ancient dwarven labyrinths they conceal. Before the Gimhak War, dwarves controlled these caves and the surrounding area as far as Idrongrun, most of Morath, and to the edges of Hangath.
Coursing its way across a vast area beneath these mountains is a mithril vein called Nâram-Zind. The entrance to the major mines of this mithril is beneath Tharam-Khâl. Dwarven spirits and constructs haunt this area and roam the interior of Bileddanul. As a result, the mithril of Nâram-Zind has not been mined since the time of the Gimhak.