Wheel Clan, Main Levels
Outside (not shown)
To get the entrance of the Wheel Clan to show up, wear the Wheel Clan spectacles on your head, and then step into the stone square next to the mountains. Once the entrance appears the first time, it will always be there, and you won't need to hang onto the spectacles.
1 - Altar to Alberich
This is a part of the Ancient Gods quest. Alberich wants lava rocks.
2 - Passage to Randver Thunder Stone
The passage (which can be difficult to see) leads to the throne room where you can find Randver Thunder Stone, the King-in-Waiting. He'll tell you that Loghaire (the king) hasn't been himself since he exiled the Black Mountain Clan to the Isle of Despair, and that he has shut himself into the Dredge, the old and dangerous part of the mines.
Be sure to talk to Randver about the Clan Wars and Lorek. Those two topics should come up automatically. Also, if your intelligence is high enough (10 is enough), you'll get a dialogue option starting with "I'm confused," and then you'll be able to talk to Randver about the Stone and the Shape. This latter topic is important for when you talk to Loghaire.
At the end of the conversation, one of two things should happen. Either Randver should show you a secret passage he has to get into the Dredge, or else he should give you permission to use the regular entrance into the Dredge (Exit F). Since you'll probably want to explore the entire Dredge anyway, it doesn't matter which entrance you get.
Finally, if Thorvald Two Stones asked you to notify the Wheel Clan of his whereabouts (on the Isle of Despair), you can do that when you talk to Randver and earn 800 experience.
3 - Vegard Molten Flow
He'll ask you to retrieve a family heirloom of his from the Dredge. When you find it (a toy train) and give it to Vegard, you'll receive 6400 experience and a miner's helmet.
4 - Erick Obsidian
Obsidian is a historian. He'll tell you about the Iron Clan, a mysterious group that created "wonders as the world has never known before or since." He'll give you a key schematic for the "Place of Iron" and ask you to retrieve the Durin Stone for him, should you find it there. This is the trigger for the Iron Clan quest (see the "Iron Clan" entry in the Other Quests section for details). When you give the Durin Stone to Obsidian you'll earn 6400 experience.
5 - Thrayne Iron Heart
Thrayne will ask you to talk to his brother Erland at the Stonecutter Clan, and try to convince him to come home. He'll even mark the location of the clan on your world map. You'll receive 6400 experience when you deliver the message. If you then come back and talk to Thrayne, you can ask for a reward and receive 200 gold. If you're feeling evil, you can tell Thrayne that his brother is coming home to kill him, and lose some alignment.
Note: Sometimes Thrayne goes to sleep and never wakes up, so you might not be able to get the quest or talk to him after you complete it.
6 - Inventor's Shop
7 - Blacksmith's Shop
The blacksmith sells mithril ore. You should also be able to find some in the Dredge.
8 - Herb Shop
9 - Garden
In the garden you'll find an olive tree, and, on the ground next to it, some olive branches. An olive branch is required for the Ancient Gods quest.
A. Exit to the world map.
B. Exit between levels 1 and 2.
C. Exit between levels 1 and 3.
D. Exit between levels 2 and 3.
E. Exit to the mines.
F. Exit to the Dredge. The dwarf blocking the stairs won't let you pass unless you have permission from Randver Thunder Stone (#2). If for some reason you don't get permission from Randver when you talk to him, and if he doesn't show you a secret passage down into the Dredge, then your only option to get in is to kill the dwarf guard. If you have any dwarves in your party, then you might want to kill the guard anyway to get his small basic platemail.