Lost to the Ages

The quest details the investigation of a lost ancient Dwemer secret and the search for four pieces of solid Aetherium.

The quest can be started by locating and reading a copy of the book The Aetherium Wars. The quest can also be started by entering Arkngthamz and talking to Katria, skipping directly to the second part of the quest.

Background
After finding a copy of The Aetherium Wars and reading it, a miscellaneous task of traveling to Arkngthamz in The Reach will appear in the Quest Log.

Upon arriving at Arkngthamz, a disembodied voice can be heard warning the Dragonborn to turn back. When continuing through the ruin, the disembodied voice will be given a name — a female Nord named Katria who will reveal that she is on the quest to find the mythical Aetherium Forge. She reveals that she died during an earthquake in the Dwemer ruin.

Katria's Journal can be found on her body. In it she expresses her displeasure that her former colleague, Taron Dreth (the author of The Aetherium Wars) stole her research to publish the book, but she says that she has the leads for the locations of Aetherium and possibly where the Forge may be located.

In her ghostly form Katria aids the Dragonborn in retrieving the first of the four Aetherium Shards needed to unlock the Forge, and thus the quest, "Lost to the Ages," begins, with the task of finding the Aetherium shards.

Arkngthamz
Reading "The Aetherium Wars" will create a mapmarker at the Dwemer ruin of Arkngthamz located in The Reach near Dushnikh Yal and Valthume. There the Dragonborn encounters the corpse of a female Nord named Katria and finds a journal on her body that illustrates her findings regarding the Aetherium Forge and the ruins of Arkngthamz.

After reading the journal, the ghost of Katria appears and explains that she wishes to complete her research and find the Forge. She attempts to discourage anyone from venturing further into the ruin and insists on accompanying them through the ruin to the Summit.

Traverse up several levels of shattered earth and Dwemer steam pipelines, fighting through Spiders, Spheres, and Falmer. Along the way Katria will comment on various enemies and will eventually comment on the spot where she fell through the ground. In dialogue she reveals that had she fallen two feet more to the left she would've landed in the water and survived.

Nearing the area where she fell through Katria comments on a log overhanging the cliff, on which is resting her bow Zephyr. Retrieving the bow, either by walking across or using Telekinesis, reveals that it is a Dwarven Bow with an inherent enchantment allowing it to fire 30% faster than normal bows.

Arkngthamz - Tonal Lock
Deep in the ruin is a large antechamber with several Falmer corpses, skeletons, and destroyed Dwemer Spheres and Spiders that lay strewn about with Dwarven Arrows. Katria explains that the Kinetic Resonators have to be hit in a specific order to unlock the door, and that when she hit them in the wrong order it caused the earthquake. Katria has the first two successfully numbered in her book. A note found on a nearby dead adventurer reveals the third. Katria advises that they all have a certain pattern.

The pattern in this room is to shoot the first on the bottom left, then the one on the bottom right, then shoot the one on the top left, then the top right, then the bottom center, and the door will unlock. Shooting in the wrong order will spawn Dwemer Spiders, Spheres, Crossbow traps, and even a leveled Centurion.

Retrieve the Aetherium Shard in the unlocked room. Katria will say that she will go out into the world searching for the remaining three and advises the reading of her journal to see where the others are located. She will appear at each subsequent location once they are found.

Note that the map arrows pointing to the shard locations are selected at random, so the order in which each Shard is located can change from what appears below.

Deep Folk Crossing
The description for the location numbered 2 in Katria's Journal, mentions a Bthar-zel, which is slightly northeast of Bthardamz, west of Druadach Redoubt, and southwest of Mor Khazgur; it is located far to the direct west of the Reach Stormcloak/Imperial Camp.

Deep Folk Crossing is a Dwemer bridge going over a river. Venture across it to the north side and up a slope to retrieve the next Shard atop a plinth (along with a Dwarven helmet, Dwarven sword, and a Dwemer Convector).

Raldbthar
The location numbered 3 in Katria's Journal, is located in Raldbthar. If the quest, "Mourning Never Comes", for the Dark Brotherhood, is started, then the ruin should be partly cleared. If not, the ruin is on a summit located east of the dragon lair Shearpoint, northwest of Gallows Rock, and southwest of Anga's Mill.

After fighting through the ruin, the second main area reached is called Raldbthar Deep Market. A room with four buttons will be reached; press the button that is second from the right to remove the metal bars. A little deeper in, there is a room filled with Dwemer gears, Falmer, and Chaurus. The area needs to be cleared by removing the blockages (skull, leg bone, human spine, and Dwemer scrap metal) from the different gears. The hardest to find is the Dwemer scrap metal embedded in a submerged gear under the water. When all blockages are cleared, the power should return to the button that lowers the bridge, and the bridge can be crossed to fight a leveled Dwarven Centurion.

After the Centurion is defeated, continue into a series of rooms where Katria will join in fighting some leveled Spiders and Spheres to locate the next Shard. Take the lift across from the room back up to Skyrim to continue the quest.

Mzulft
The location numbered 4 in Katria's Journal, is where the next Shard is located, in the Dwarven Storeroom right before the entrance into Mzulft. It is found along the western side of the mountains of Eastmarch, and is quite a distance southeast of Windhelm, and a short distance directly north of Cragslane Cavern.

If the chamber hasn't already been cleared, it's just a room with two Apprentice locks and one Expert lock filled with Dwemer metals, scraps, cogs, gyros, Dwarven Metal Ingots and a Dwemer Convector. Only two out of three doors are needed to be opened in order to retrieve this Shard and the rest of the loot.

Regardless of what order the Shards are found in, upon finding the fourth Shard Katria will state that all that is left to do is find the Forge.

Aetherium Forge
Upon consulting Katria's Journal, the fifth point shows the Forge to be west of the Lake Honrich. In reality, it is slightly southwest and much farther. It is the Ruins of Bthalft, which is located southeast of Ivarstead and east of the Rift Imperial Camp.

Upon arriving at the Forge location, bandits will attack. After dispatching them, place the Aetherium Shards on a Dwemer Globe that Katria points out. The ground starts shaking violently, and Katria advises standing back on a wooden platform. The globe will shoot up into the sky and reveal a lift underneath.

(Note: at this point, Katria may become delayed on the site. Wait for her; do not revert to another save, just sprint into her to move her)

Take the lift down into the abandoned Dwemer ruin and find the way through, where Katria will remark that no-one has set foot there in over four thousand years. Torches and beacons automatically light the way.

At the main antechamber before the Forge, a massive locked door will be in the way. Above the door are two Kinetic Resonators. Shoot them both, and the Forge Room will be opened.

The Forge Room
Upon entering, steam will be rising from a grate in the center; use the valves to shut off the steam and approach the Forge. Upon the approach, a new objective becomes evident: defeat the Forge's Guardians, who will appear and immediately attack. Fight off Dwemer Spiders, Dwemer Spider Guardians, and Warped Dwemer Spiders (whose approximate strength are a cross between run-of-the-mill Spiders and Guardians)

After defeating the Spiders, Dwarven Spheres, Sphere Guardians, and Warped Spheres will join the fray, and the steam will turn back on. Using the valves, turn it off again and return to the fight.

It is recommended to fight on the top decks near the valves and use the steps as a funnel. Katria will either dual wield daggers or use Zephyr. A good tactic is to make use of the Unrelenting Force, Fire Breath or Frost Breath, and area of effect Destruction magic to whittle down the Animunculi's strength.

After defeating these, The Forgemaster will appear out of the lava behind the Forge. It is the most powerful Dwarven Centurion Master known, and can breathe fire (instead of steam like other Centurions) and is resistant to fire damage.

After defeating the Forgemaster, Katria says to get some supplies from the chest near the Forge (unless some were brought along) and the Aetherium Forge can be used to craft one item from the Aetherium Shards.

There are also, on either side of the forge, two gates that seem to just lead into the lava. If Become Ethereal is used, it can be swum in. If by any chance Ahzidal's Boots of Waterwalking from the DLC are possessed, the lava can be traversed, but fire damage will still be taken.

Using the Become Ethereal shout, take the left path up to a small chest and another on the right. These paths lead to an overlook position of the forge so once the enemies start pouring in, it's a good place to shoot them from.

Straight back from the forge is a large chest. To get to it, use the Become Ethereal shout to swim from the right side of the forge to the small island in the middle of the lava, then turn slightly left and the small alcove with the chest in can be seen. It is also a good idea to have resist fire potions because it is a long swim, and the islands are small. Full magic resistance will work as well. Also using a Resist Fire potion of 60% or higher and Whirlwind Sprint to reach the middle island is advised. Stop and restore health and allow the Shout capability to rebuild, then drink another Resist Fire potion and Whirlwind Sprint to the chest. Another Resist Fire potion and Whirlwind Sprint will allow access to the left ramp back to the forge.

The Aetherial Equipment
The Dragonborn can choose from three pieces of equipment. However, only one can be chosen.
 * Aetherial Crown: allows the Dragonborn to have two Standing Stones powers (the crown must be worn to keep the previous standing stone power)
 * Aetherial Shield: enemies are turned ethereal for 15 seconds when bashed so they cannot be harmed or harm the Dragonborn
 * Aetherial Staff: spawns a Dwemer Spider or Sphere for 60 seconds.

After forging the selected item, Katria comments on whichever item which was chosen to be forged, and mentions that there most likely isn't any more Aetherium in Skyrim. With a sigh of relief, she thanks the Dragonborn and expresses that she is finally at rest, and after a few final departing words, she fades away, to take her place among the honored in Sovngarde. This completes the quest, and awards the Achievement (Xbox360) or Trophy (PS3) "Lost to the Ages".

Katria's Last Words
When the quest is complete, Katria says,

"And now... I think I can rest. Farewell, my friend, wherever your travels take you."

She then disappears (with a bow of gratitude), bound for Sovngarde.

Post-quest activities

 * After completion of Lost to the Ages, Taron Dreth can appear as a Random Encounter along the roads with three mercenaries in tow. If the Dragonborn has one the items forged out of Aetherium (the Aetherial Crown, Shield or Staff) in their possession, Dreth will ask the Dragonborn how they acquired this item. He will initiate combat with the Dragonborn no matter which dialogue option is chosen.

Trivia

 * As possibly one of the longest quests in the game, the quest has the Dragonborn investigating an ancient Dwemer secret, during which they search for four pieces of Aetherium spread out across Skyrim. The quest takes them all across Skyrim, delving deep into five Dwemer Ruins, which include Arkngthamz, Raldbthar, Mzulft, Deep Folk Crossing and the Ruins of Bthalft.
 * While Katria does appear to be a ghost, she still triggers the Detect Life and Heal Other spells.
 * Katria, the ghost of a woman aiding the Dragonborn by telling them where fragments of an item are located, scattered all over the country, is very reminiscent of Ria Silmane from the original game, whose ghost led the Eternal Champion all over Tamriel to find pieces of the Staff of Chaos to destroy Jagar Tharn.
 * If the Dragonborn takes the armor from Katria's corpse, her ghost will ask them to pay some respect to her body: "Really? You had to take the armor? Come on, leave me with a little dignity..."

Achievements
Затерянное в веках Perdue dans les Âges Verloren in der Vergangenheit