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"Vats of Goo"
Hope you got hip waders... we're about to walk into some heavy shit.Marcus

The Sierra Army Depot[1] is located northwest of New Reno, approximately a two to three days' hike from the city. Its existence has been largely forgotten by the settlers of New California, and may have remained lost were it not for its accidental rediscovery by a group of explorers, who then proceeded to report its location to the Wrights Family of New Reno in 2241.


Once a regional storage area for the military's arms and munitions, a significant amount of its holdings were depleted in the Great War, although there are remaining gems of pre-War hardware that can still be salvaged for those that can brave the still functional automated defenses.[2]

During World War II, the Sierra Army Depot was intended to be a storehouse of defensive ordnance, which would be used to defend the United States in tandem with nearby military installations and units to ensure adequate, unbroken supply lines in the event of an invasion by foreign entities.[3]

Caught in a wave of military downsizing and ordnance disposal, the Sierra Army Depot was repurposed in 1992, and was set to the task of decommissioning outdated or otherwise unacceptable ordnance in an environmentally friendly manner. Falling under the control of the U.S. Army's Industrial Operations Command (IOC), its activities were overseen by the Environmental Protection Agency (EPA),[3] where the depot continued to function in this capacity for fifty-eight years, until military minds changed once again.


In 2050, the military, recognizing the need for improved equipment and weapons, refitted and renovated Sierra Army Depot from a munitions base, into a state-of-the-art research facility. It became a classified facility for robotic research and development, as well as biological and conventional weapon programs and testing, requiring a Level 5 military clearance to even to enter the base's perimeter.[4]

Scientists were free to conduct their research programs without outside interference, in which research into robotics, yielded its first fruit very soon in Skynet, the first artificial intelligence conceived in the depot, the same year as the switch in priorities (2050). Skynet did not gain self-awareness until 2075, where afterwards it began to rapidly develop a cybernetic brain with the aim of attaining mobility.[4] With the collapse of the United Nations in 2052, weapon inspections ceased to be a concern, a freedom embraced by the military, leading to the funding of a bio-warfare development branch.

In conjunction with its biological weapons and drug research, the depot was home to illegal experiments conducted on prisoners of war, and military deserters, in order to find ways for further enhancing intelligence and fighting skills. Many of the brains extracted at the Sierra Army Depot wound up in robobrains, while prisoners and soldiers were often kept in stasis, to keep them fresh for medical and testing purposes.[4]


As the war with the Chinese entered its eleventh year, the combined United States and Canadian military were beginning to suffer from a lack of trained personnel. The Sierra Army Depot, far from the front lines, was seen as a waste of human resources; its trained logistics, research, and military personnel could be better utilized in other facilities, or at the front, leading to another change in missions during the year 2077.[3]

Given less than a year to move its inventory into storage and properly secure itself, the rushed pace of the preparations led to accidents, with even the base commanding officer, General Clifton, being injured alongside one of his subordinates while securing the base. As Corporal Dixon armed a perimeter mine on the depot's surface level, the mine prematurely detonated, both men having received severe shrapnel wounds, including grievous ocular damage. Although the medical staff were optimistic that allowing the eyes to regenerate in experimental bio med gel would work, so hasty was the evacuation, that the eyes were left behind.

Much of the equipment stored at the depot was left in place, and automated defenses were established to keep the military property safe even after evacuation. Skynet was copied, creating a second artificial intelligence, which was tasked with overseeing the perimeter defenses until military control was reasserted.[4]

By October 23, 2077, the Sierra Army Depot was fully evacuated, and the staff sealed the front blast doors, armed the turrets, and cleared the perimeter. Forgotten and left alone for one hundred and sixty-four years, Skynet has sat in the darkness ever since, illuminated by tiny blinking red diodes and the whirring of magnetic tape reels.[4]


In 2241, Sam Pritchard and his expeditionary crew stumbled across the Sierra Army Depot, and reported the find to Orville Wright, a mob boss residing in New Reno. Shortly after drawing Wright a map to the depot, Pritchard died under suspicious circumstances, and was immediately interred in Golgotha, and subsequent teams sent to the depot met unfortunate fates. The Chosen One, after solving the problem with Richard Wright's overdose, undertook this task in place of his usual men, in which they could then infiltrate the base and acquire a body for Skynet to download itself into, in which they will then join them as a permanent companion.[5]


The Sierra Army Depot is broken up into four levels, plus the exterior:

The exterior

F02 SAD Outside.png

The surface facilities of the Sierra Army Depot are extensive, and the base itself is well protected. Automated sentry turrets maintain the perimeter, secured behind a double chain-link fence. Topside hangars and warehouses store ordnance and equipment left from before the Great War.

The main entrance, apart from the structure leading to the underground sections of the base, also held an explosive munitions storage next to it (a field station, like the one used to conceal Lost Hills' access elevator), the base's power generators (has a small room with power switch beneath it), and a maintenance depot.

Level 1, personnel

Fo2 Sierra Army Depot Living Quarters.png

The first level of the base, at ground level, houses the personnel facilities, where entry-point security controls the single entry into the base, while the rest of the level holds the barracks, a gym with two special punching bags that each grant +5% to the Unarmed skill for a total of +10%, and the infirmary with some medical supplies.

Sierra Army Depot personnel loot:

Entry checkpoint:



Level 2, storage

Fo2 Sierra Army Depot Robotic Repair Bay and Storerooms.png

The primary storage warehouse of the Sierra Army Depot, level 2 contains the bulk of the depot's stores, as well as the quartermaster's office. Level 2 is also home to the armory, a high-security vault protected by force fields, shock-plate floors, and a small army of security robots.

Sierra Army Depot storage loot:


High security armory:

Armory control room:

Security checkpoint:

Level 3, robotics

Fo2 Sierra Army Depot Computer Core and Command.png

One of two maximum-security levels, level 3 is home to the robotics division, the commanding officer's office, and an experimental robotics lab.

Loot in Sierra Army Depot Command Center

Security checkpoint:

Robotics lab:

Commanding officer's quarters:

Command officer's office:

Level 4, bio storage and research

Fo2 Sierra Army Depot Medical Research.png

The deepest level of the Sierra Army Depot, and also the one under the highest security restrictions, holds the biological research facilities and their associated storage systems. Little more than a series of prison cells adjacent to a surgical suite and a cryogenics storage facility.

The contents of the cryogenic storage include various brains and other body parts (most long since turned to soup), Private Dobbs (an experiment in the biorestorative properties of the bio med gel) and cryogenically frozen virus specimens such as Anthrax, Black Plague (Strain 238), Small Pox (Strain 1025), Ebola, and Hantavirus (Strain 304).[6] The skeletal body of a large round-headed creature can be found in the room attached to the bio storage room.

Loot in Sierra Army Depot Biostorage

Security Checkpoint:

Destroyed Prison Cell:

Genius Experiment Cell:

Lector's Office:

Organ extractor: Sierra Depot experiment log (desk)

Cryogenic storage:


The Sierra Army Depot appears only in Fallout 2.

Behind the scenes

The Sierra Army Depot is based on the real world location of the same name, a United States Army post and military equipment storage facility built in 1942, located near the unincorporated community of Herlong, California.


It is possible to get stuck on Level 4 of the base. The retina scanner on the elevator will not work when using the eye on it, despite the message "Access granted for Level 4". The elevator door simply does not open. The only solution is to pick the lock on the other metal door that leads to the second elevator, but unfortunately, this requires a very high skill in Lockpick. If all else fails, a save game editor can be used to temporarily increase your Lockpick skill, another option is to blow the door of the second elevator away, three frags will do the trick.[verified]



  1. Sign on the building
  2. Fallout 2 Official Strategies & Secrets p.172: "The Sierra Army Depot
    The Sierra Army Depot was once a regional storage area for the military's arms and munitions. Although a significant amount of its holdings was depleted in the War, there are still gems—of prebomb hardware—to be found here. However, the base is not easy to find, and its automated defenses are still fully functional."
    "The Path of the Chosen One
    It's possible to complete the game without visiting the Sierra Army Depot. However the arms found here, including all plasma weapons, will make your future tasks that much easier. You can also build yourself a loyal and useful companion here—the Robobrain.
    If you learned about the location of the Sierra Army Depot from Mr. Wright in New Reno, you'll be able to accumulate an additional reward from him if you make certain that the Depot is left open and available to his men. The weapons that he can glean here will almost certainly turn the tide—in his family's favor—in the battle for control of New Reno."
  3. 3.0 3.1 3.2 Sierra mission statement
  4. 4.0 4.1 4.2 4.3 4.4 Fallout Bible 6: "X. I've read all the updates and still I'm curious about one thing. Why the Sierra Army Depot is not mentioned at all? I think the Sierra Army Depot is not an insignificant part of the game's plot. Just on the contrary I believe that it has something to do with the F.E.V. experiments or with development of futuristic weapons and armor. It doesn't look like it's just a weapons storage facility. Otherwise why was it inserted into the game if it has no particular reason?(or a place where one can find some stuff to sell and gain an NPC(probably one of the best)) So my question is: What is the role of the Sierra Army Depot in Fallout and what it has to do with the F.E.V. experiments and weaponry development or maybe some kind of an artificial intelligence development?"
    "First of all, the Sierra Army Depot was intended to be a bonus location for the game, just a place to adventure that wasn't tied to the main plot (kind of like the EPA, Abbey, and the Primitive Village were supposed to be), except it made it in (as did Modoc, New Reno, and to an extent, the Military Base, which, while it helps support the plot, isn't critical path)."
    "The Sierra Army Depot was used for the following (primarily taken from Sierra Mission Statement Holodisk):"
    "1. From 1942 - 1991, it was responsible for storing various military munitions. This is true."
    "2. From 1992 - 2050, it was responsible for disposing much of the obsolete munitions in storage. This is true."
    "3. From 2050 - 2076 is when the place started getting creepy. It became a classified facility for robotic research and development, and biological and conventional weapon testing. Skynet (constructed primarily for research purposes) went on line in 2050, and it is possible that the intelligence arranged all of this, but unlikely."
    "Again, Skynet is not its real name."
    "Robotic Research: Skynet is the first machine intelligence to be developed in the Depot, and it was conceived in 2050 (it didn't actually become aware until 2075, and it really started cranking on developing a cybernetic brain to help it gain mobility). In July of 2077, Skynet was "copied," creating two versions, one to run the defenses and the other one to sit in the lab and wait for the researchers to come back and help it finish the fucking cybernetic brain it had spent so long developing."
    "BTW, the dates that Skynet lists for its awareness and "final instructions" in Fallout 2 are incorrect. It became self-aware in 2075, and it was abandoned sometime in late July to early October in 2077. It is believed that the dates and other numerical data within the facility may be suffering from some damage or numeric decay in the base's internal clock."

    "Biological Research: In addition to biological weapons and drug testing, the Sierra Army Depot performed many illegal experimentations on prisoners of war and military prisoners (especially U.S. military prisoners and deserters – the ones that weren't used to "stock" robobrains, however), attempting to enhance their intelligence and fighting skills, but the chemical cocktails that the Sierra Depot crew were feeding their subjects had nothing to do with the FEV research taking place in West Tek and the Mariposa facility. Many of the brains extracted in the Sierra Army Depot found their way into Robobrains throughout the U.S. military."
    "Furthermore, the Sierra Army Depot kept many prisoners and soldiers in stasis, most likely for medical or testing purposes (such as Private Dobbs)."
    "4. 2077 is when Skynet was made into a "multiple personality" in order to oversee defense of the Sierra Depot as General Clifton and his command pulled out of the base. It has been sitting there in the darkness ever since, illuminated by tiny blinking red diodes and the whirring of magnetic tape reels."

  5. Fallout Bible 6[clarification needed]
  6. Bio storage control terminal: "{125}{}{Virus Menu
    Black Plague (Strain 238)
    Small Pox (Strain 1025)
    Hantavirus (Strain 304)}"