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 (1490 - 1503).
Bileddanul is dotted with thousands of caves, hundreds of dead mines, and dozens of ancient Gimhak ruins. These places serve as the abodes of bugbears, wandering constructs that once defended Gimhak, tribes of kobolds, sometimes dragons, and many other types of beasts and monsters. Many have escaped their pursuers by entering the ancient dwarven labyrinths of another age. Before the Gimhak War, dwarves kept the peace in this area. Under new masters, the Bileddanul highlands has become wild and frontier-like. The cave and tunnel network is vast, stretching as far as Idrongrun, under the Morath Forest, 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.