This buried, forgotten and half-ruined former dwarf forge can be reached in two ways. One is through a cave entrance in the north-east and the other through a raging river in the east. In the northern chambers are the forges and in the south the small throne room and the treasure chambers of the Grand Blacksmith Mekranaz.
Hooks: The fortress of Mekranaz is bigger, so the adventurers get lost here. Or they have to salvage something from the forge (the classic). Or they also flee to this area and then have to face their pursuers.
Here is the map