Post Greyhawk Wars: 585 CY
These great western peaks stretch northwest to southeast, with the Barrier Peaks angling to the northeast and the Joltens as a central spur. The Sulhaut mountains extend westward, dividing the Dry Steppes from the Sea of Dust. The small range of Ullsprue Mountains within the Plains of the Paynims are loosely connected. The central mountain spine and certain peaks within the Jotens are probably the highest in the whole Flanaess.
The main mountain bodies here have always been plagued by giants, with fue giants more dominant as one enters the Hellfurnaces. The Hellfurnaces, as their name suggests, are the major volcanic region of the Flanaess. Creatures such as salamanders, hell hounds, and fienewts abound there. Below the mountains, the drow, kuo-toa, and illithids of the underdark struggle with each other and use the surface races as their pawns from time to time. Many humanoids, ogres, and trolls also lair in the Crystalmists. The great Crystalmist-Hellfurnace spine is really a hive of evil.
The Crystalmists are also home to mountain dwarves who mine the rich ores of precious metals to be found therein. With the fall of Geoff, however, they are increasingly isolated. Their brethren in the Barrier Peaks are better placed, since they continue to trade with Ket
The Crystalmists and Hellfurnaces contain many marauding monsters in addition to social creatures and humanoids, and are extremely dangerous. Only well-equipped and powerful adventuring parties risk traveling there. Some people still do, because of the wealth of ancient ruins and treasures these mountains are said to hold; the tombs of great wizards, focuses of powerful elemental magic and gates, ruined evil temples to nameless gods, and much else