Upon entering the ruins you will see a large room with a flame trap blocking the doorway. Use Whirlwind sprint to go through it without getting burned, and you will see Alain Dufont (behind an expert locked gate), otherwise do the following. Down the hall and to the left is a bandit sleeping on a bedroll. Even further will be a charred skeever impaled by a pole that is set up infront of the dwemer flame trap so it willl cook. Take a left down this hall and fight through three more bandits.
After these bandits are dead, head through their room, and turn right to fight 3 more bandits and Alain Dufont. Alternatively, pick the master lock on the gate, and head through it to find some dwarven crossbow mechanisms aimed at the bandits. Pull the levers next to each one of these to activate.
After the bandits are dealt with, head into the next room (underneath where the crossbow contraptions are) to find some more loot, mostly behind a locked gate. Through the next door and around a corner lies a dwemer sphere and then another door. The next large room contains loud gears, a spider worker, and two more dwemer spheres.
The next door should be open, and leads to a hallway with a spider worker, and then stairs with a double helicopter blade trap, which should shut off automatically after you defeat the spider worker. (Note: The blades tend to be very glitchy, so save before going through the open door.) If the blades don't stop after defeating the spider worker, you can traverse it by getting next to the parts of wall where they can't reach. Once the blades are past, you can run over to another part of the wall to get to the top. Up the stairs is a pusher/flame trap, and 2 more dwemer spheres. Up the stairs leads to a hallway with two spider workers and, at the end, an elevator to the Raldbthar Deep Market.
Head down the corridor to a large room with many Falmer and two Skeevers in a pen. Head up the stairs on the far side, and then down again to a button that drops a draw bridge. Proceed up and across until there is a room with 4 buttons and a blocked hall to the left. The button on the left will activate a fire trap, the second from right will open the gate. Next is a room with a few levelled Falmer and two Chaurus behind a locked gate to the left. There is a bridge with a button labelled "unpowered". Go to the stuck gears in the room and remove various bones jamming the cogs to power the bridge. Note that one set of stuck gears is located beneath the bridge underwater. After unjaming all the gears, press the button on the bridge, which will activate a Dwarven Centurion. After defeating it go thorugh the door that was behind it
There is another section with a chest above the pathway before the room with the final boss. Climb the pipes and use the Whirlwind Sprint to get across to the ledge.
The Centurion then rises on the other end of the bridge. Keeping at safe distance and using a ranged attack (bow or spells) is advised; the Centurion's steam attack can be devastating. One strategy is to run into a Falmer nest, defeating its attack range. It is also possible to press the button once more when he is on the tip of the bridge to send him to the ceiling; At that point, get his attention, and he will fall into the water and die.
Another tactic to kill the centurion, is the get behind the door he comes out of. Open it quickly and use a conjuration spell to distract him. While he is distracted kill him without harm. Having the Conjure Dremora Lord spell or Sanguine Rose makes it possible to kill the centurion in seconds without ever having to go anywhere near it. Simply cast its spell into the centurion's chamber as soon as the bridge drops. The Dremora will finish the Centurion off before he even takes a step, allowing entry to the door behind it.
The various bones jamming the gears powering the bridge may spawn on the floor or near the gears, instead of wedged in them.
The objects jamming the gears may not respond to the player. Backtracking to the area that the bandits were in and then returning may fix this. (Xbox360)
If the player returns to the dungeon upon completion, the jammed gears may reset but the objects jamming them might not. This makes it impossible to access the end of this dungeon after reset.
On PC, you can type tcl in the console to disable clipping and fly through the bridge. Until a bugfix is released this can at least be used as a workaround.
A possible method for avoiding the afforementioned bug is to exit the dungeon from the front. Then completeDark Brotherhood Contract For Muiri by returning to her. Upon completion, you may now go north of Winterhold in search of Septimus Signus's Outpost.
The boss, who would normally attack, may follow you without attacking.
When trying to leave Blackreach through the Raldbthar Dwarven elevator to Skyrim, the game may freeze. (Xbox360)Raldbthar Deep Market
Sometimes upon entering the ruins after doing the Dark Brotherhood mission you will not be able to proceed deeper into the dungeon due to an invisible wall.
When entering the water to un-jam the cogs the game might crash, save first. (ps3)
Sometimes, when unable to remove the items to power the button, exiting the area to the previous one and then returning does not fix the problem. It can glitch even more and cause the pieces to be immovable objects on the floor. (PS3)
When entering the left hand side of the pool, if you swim against the wall on the left and turn around, you can see a strange half-pillar which is only visible and solid from this side.
Raldbthar
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Added by Bsua
