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Scavengers report hulking individuals moving around Hidden Valley after dusk, but have been unable to identify them due to low visibility.

Hidden Valley is a military installation nestled between hills and rocks roughly northeast of the New California Republic Correctional Facility (NCRCF) and southeast of Sloan. The valley is home to numerous bark scorpions and the remnants of the Mojave chapter of the Brotherhood of Steel that once occupied HELIOS One before being defeated by the NCR during Operation: Sunburst.


DERVISH camouflage system in Hidden Valley.

Once one of the most pristine natural basins in the McCullough Range, Hidden Valley was a destination for hikers wishing to experience the untamed wilds of Nevada. However, with hostilities escalating across the globe and the Sino-American War continuing with no end in sight, it fell prey to the military-industrial complex. The United States Air Force declared it a testing range, surrounding the area with a chain-link fence, forbidding photography, and then completely forgot about it. The secrecy of project likely so buried in bureaucratic red-tape that no one who could've used it knew about it. To the casual observer, it was just a stretch of federal land, cordoned off, abandoned, and covered in graffiti protesting the futility of the Sino-American War.[Non-game 1] The perception changed little after the Great War, with wastelanders seeing it as little more than a stretch of particularly desolate wasteland, home to derelict bunkers, mute intercoms, and bark scorpion.[1]

Of course, this was all a ruse. The USAF selected the remote Hidden Valley to establish an independent, self-sustaining underground bunker, using the same technology used at Raven Rock. The facility was intended for use by high ranking personnel and other VIPs as a shelter and command center in crisis situations. The bunker was built several hundred feet (over 100 meters) below ground, beneath multiple layers of reinforced materials in order to ensure that nothing short of a direct hit by a bunker-busting megaton nuclear weapon could threaten the installation. Such capacity was believed to be well outside the United States' closest competitors, but the bunker was provided with additional protection in the form of the DERVISH camouflage system. This complex network of industrial vents and fans generated an artificial sandstorm using the loose soil within Hidden Valley, which was supplemented by a combination of aluminum and silicates to create what was essentially a giant cloud of chaff, interfering with remote guidance systems. Together with the Black Mountain radar array and its electronic countermeasures, targeting the Hidden Valley bunker network was effectively impossible, assuming its existence was known in the first place.[2]

The bunker itself was furnished with every facility necessary to its continued operation in the event of a catastrophic event, including a variety of living quarters ranging from bunk rooms to individual chambers, a fully stocked clinic capable of carrying out complex surgeries, vast store houses, shooting ranges, workshops, research labs, a virtual reality training system, everything needed for prolonged isolation. In order to ensure longevity, the bunker was fitted with a CANDLE fusion power system. Powering all the bunker's systems, it was a mature and tested technology. Although newer designs offered a higher power output, the CANDLE offered reliability and longevity, capable of powering the bunker for an estimated 752 years (until ca. ~2700).[2]

The fact that Hidden valley survived the Great War is a testament to its countermeasures and Robert House's defense of the Mojave. Over the next two centuries, the bunkers were abandoned and fell into disrepair, with large parts of the installation caving in due to lack of structural maintenance, salvaging, or design. It wasn't until the 2260s and the arrival of Elder Elijah at the head of the newly founded Mojave Chapter that it gained a new lease on life, set up as an auxiliary location and fallback point for the chapter, second to Helios One.[3] It was "promoted" to a chapter bunker following the disastrous Operation Sunburst in 2276 when the chapter was routed from its stronghold at Helios and forced to flee into the McCullough Range. The new Elder, Nolan McNamara, instituted a lockdown: All Brotherhood members who made it into the bunker were confined inside, while those outside the bunker were prohibited from returning to prevent the NCR from tracking the chapter down. Only a select few were permitted to leave to procure essential supplies or to patrol the Hidden Valley at nighttime, under cover provided by the DERVISH.[Non-game 2]

Though the Brotherhood prepares its members for extended seclusion through its ascetic training, the situation is slowly deteriorating. Five years after the loss of Helios, many of the Knights and Paladins promoted to fill in the gaps in manpower have no real combat experience, relying on virtual reality simulations and firing range exercises, the chapter is incommunicado to the rest of the Brotherhood, and internal tensions are simmering beneath the surface as Head Paladin Hardin is looking for a way to oust the current Elder and implement his policy.[4] Unbeknownst to all but the Elder and Knight Lorenzo, the bunker itself is slowly failing. The DERVISH system was not designed for constant use and the accumulation of enhanced dust in the ventilation system is taking its toll on the bunker's life support systems. Simply put, if the systems are not fixed, the bunkers would become uninhabitable in short order. The Elder attempted to send scouting parties out to retrieve the parts, but a lack of intel (caused by the skewed priorities in the Elijah era) and local hostiles resulted in the loss of all patrols.[5]

Finally, the single biggest threat to Hidden Valley and the Mojave Chapter are the powers that vie for control of the Mojave. Mr. House and Caesar want the Brotherhood removed from the picture, seeing them as a threat to their control of the region, while the Republic is willing to sign a truce in exchange for military aid (if the Courier plays their cards right).[5][6] Hiding is not an option, as even if the life support systems were restored to full functionality, all factions are aware that the Brotherhood is still lurking somewhere in the McCullough Range. After all, it only took House two years to figure it out, after losing a single Securitron per annum in the vicinity of Hidden Valley.[7]


The view of Hidden Valley in a westerly direction. The bunkers surround the center of the valley, located in each of the cardinal directions.

The Hidden Valley is a large basin located east of Sloan, between Black Mountain and the NCR Correctional Facility. It's easily identifiable by the damaged fencing surrounding it, four distinct bunkers buried under the sand, and working industrial fans, on top of several bark scorpions and occasionally larger radscorpions preying on them. There are four bunkers in total, located in cardinal directions along the edges of the area. There's a large break in the fence to the south-east, leading to the Scorpion gulch and the El Dorado Valley beyond.

Four Brotherhood of Steel Paladins will leave the western bunker for a patrol, covered by the DERVISH camouflage system, between 01:00 and 03:00 patrolling around the bunker until just before dawn.

East bunker

This ruined bunker contains a pair of skeletons on a sleeping mat with a bottle of wine and a suitcase, which suggests a sad story. There is also a campfire. The Easy locked door in this bunker hides a hundred 5mm rounds and anywhere between 20-24 5.56mm rounds.

North bunker

Perhaps the most intact bunker, aside from the one leading to the installation. It contains ancient supplies illuminated by blue fluorescent lamps and an Average-locked door leading to 2 mini nukes, a stimpak and some 5.56 mm ammunition.

South bunker

A largely derelict bunker, it has been recently taken over by an NCR Ranger, who plans to turn it into a safehouse in order to watch the Interstate from the safety of the Hidden Valley. The camp contains two grenade bouquets can be disarmed in the entrance hallway hanging from the ceiling, and a third out of reach near the middle of the entry room. The entry room also contains a sleeping pad and a sack, along with a journal indicating that someone is using the bunker as a safe house. The Hard locked door here opens the way to three ammunition boxes, a mini nuke hidden under a tin plate, a steam gauge assembly and two pieces of scrap metal on the right, and some frag grenades and 5.56mm rounds on the left.

If the Courier enters the west bunker without Veronica as a companion, they will be assigned a task to remove an NCR ranger from this bunker. After dealing with the ranger OR making contact using Veronica OR answering the summons for ED-E, a trip-wire triggering the grenade bouquets will appear in the entry room door, along with more entry room grenade bouquets (one to the left can be disarmed). The entrance hall grenade bouquets previously mentioned will also respawn if disarmed earlier.

The Ranger will appear if Still in the Dark is activated and the Brotherhood forces the player to resolve the situation with him.

West bunker

Main article: Hidden Valley bunker

The Brotherhood bunker known as Hidden Valley bunker.

The fourth bunker contains the hidden elevator to the facility, easily identifiable by a tree stump on top of the entrance. The entrance hall has little in the way of interest, while the door into the bunker is protected by a Very Hard lock. The player can obtain access by:

Notable loot

  • 3 mini nukes: In the northern and southern bunkers, both behind the locked doors.
  • A hollowed-out rock with a heart and anti-bomb symbol: Located in front of the fast-travel marker, the rock is right in front of the player upon fast travel.

Related quests


  • The south bunker will be empty when entered unless the Still in the Dark quest has been activated, which will cause the Ranger Dobson to appear within near the campfire.
  • Going into the Brotherhood's bunker while wearing any type of NCR armor will automatically turn the entire bunker hostile, even with Veronica present.
  • When entering the Brotherhood secure area using the passphrase, the NCR Ranger portion of the Still in the Dark quest will immediately start. All weapons and armor will be taken but will be given back once the task is completed.
  • If the lock is picked, the Brotherhood soldiers will not be hostile, but when leaving the bunker again, all companions will be locked in the bunker, meaning the Very Hard locked door must be unlocked again to get them back. The only other way to get them back is after the completion of the Still in the Dark quest.
  • If the self destruct system is detonated, the DERVISH camouflage system is disabled and smoke rises up out of the air shaft vents scattered around the bunkers.
  • In the south bunker there are grenade bouquets hanging from both the ceiling at the bottom of the staircase, and in the center of the main room. If entering the bunker after receiving the related task as part of Still in the Dark, the traps will be gone.
  • The interior of the Brotherhood's bunker bears a striking resemblance to Raven Rock from Fallout 3.
  • Four Brotherhood of Steel paladins will regularly go out on patrol between 1 AM and 3 AM, guarding the area near the bunker until just before dawn. If they are encountered leaving the inner bunker, the player character will be forced to start the Still in the Dark quest, unless the player character has Veronica in their party. If the player character talks with them at this point, they will speak as if they are already a member of the Brotherhood. If the player character dismisses Veronica at this point, the paladins will turn hostile.


Hidden Valley appears only in Fallout: New Vegas.

Behind the scenes

  • Megan Parks was responsible for layout, prop placement, decoration, terrain shaping, and vistas in this location.[Non-game 3]
  • Hidden Valley is located in the same geographical area as the real world Hidden Valley in Clark County, Nevada.
  • The Hidden Valley bunkers closely resemble storage bunkers overlooking Area 51 at Groom Dry Lake in Lincoln County, Nevada.
  • Originally, the player was supposed to be able to spy on Taggart for Schuler and discover a PTSD (Post-Traumatic Stress Disorder) virtual simulation, according to the following script attached to VDialogueHiddenValleyLindaSchulerTopic009 (I don't appreciate how much harder I have to work to cover for his tendency to focus on his personal projects. I try not to think too much about his personal proclivities.:
This might not be necessary. I might be able to
add a top level topic for telling her what you
found out and simply have it check to see if you
discovered the PTSD sim.
set VDialogueHiddenValley.SpyingForSchuler to 1
  • It was planned for the player to be able to use the VR pods here, probably to play a VR simulation where the player must defend Hidden Valley from Enclave intruders. There is a VR pod called HVPlayerPodREF and a message called HVGameScoreMessage that tracks a variable to display the number of kills in the VR game. There are also cut notes relating to Melissa Watkins that show she is playing the VR sim at a deliberately lower difficulty level. There is also an unused computer terminal called HVPodSimSelectionTerminal that seems to relate to the above.
  • There are unused AI packages for NPCs of both sexes to use the relevant bathrooms here.


  • PCPC Playstation 3Playstation 3 Xbox 360Xbox 360 After wandering through the bunker and exiting out into the wasteland again, 2-5 bark scorpions may sometimes spawn right outside of the bunker that was exited. In the later patches, bark scorpions spawn less frequently.[verified]
  • PCPC Playstation 3Playstation 3 Xbox 360Xbox 360 In the hill paths leading to Hidden Valley, it is possible to encounter deathclaws from Quarry Junction, including the deadly deathclaw alpha male. It may pop out from under the hills or rocks.[verified]
  • Playstation 3Playstation 3 Xbox 360Xbox 360 If fast-traveling to Hidden Valley and arriving just before sunrise, the ground may turn black and the distant surrounding areas will turn into a hazed green. The ground will eventually change back into color, although the screen will turn completely black afterward, and the game will need to be restarted. A way to avoid this is leaving Hidden Valley before the screen changes. This is most likely a glitch from the sandstorm that flows throughout the area at night.[verified]
    • This may also occur if the wait function is used while in Hidden Valley.[verified]
  • PCPC A Securitron Mk I may spawn in the bunker, blocking the player character. [verified]
  • PCPC Xbox 360Xbox 360 Sometimes an evolved centaur will spawn right next to the player character upon fast travel to Hidden Valley. This can begin to happen after killing Moe and the other various centaurs in the crater near Black Mountain.[verified]
  • Xbox 360Xbox 360 It is possible to get infinite ammunition from the supply footlocker. By using the ammunition to craft something in level two and then returning, the footlocker will be resupplied. Simply exiting and re-entering the bunker will also respawn more ammunition.[verified]
  • Playstation 3Playstation 3 It is possible to go through the ruins blocking the entrance to the bunker. It is impossible to leave once inside, however.[verified]
  • Xbox 360Xbox 360 Victor can spawn in the bunker when waiting by the ammunition case.[verified]
  • Playstation 3Playstation 3 During the tutorial quest, Sunny Smiles may transport to the valley.[verified]
  • PCPC Xbox 360Xbox 360 When approaching the valley at night when Cateye, or with the Friend of the Night perk, the night vision effect will suddenly fail and the screen will become much darker. This can happen at distances well over 100 yards away and can be surprising when coming from directions where the valley itself cannot be seen. This may be an effect of the camouflage system and can be fixed by simply walking in another direction. [verified]
  • Xbox 360Xbox 360 When killed, the bark scorpions may glitch through the ground and disappear sometime later.[verified]
  • PCPC Xbox 360Xbox 360 When disarming the grenade bouquets in the south bunker while using Turbo, sometimes they can be successfully disarmed (adding the three grenades into the inventory), yet the trap will still trigger, dropping three more exploding grenades. [verified]



  1. Hidden Valley bunker terminal entries; Terminal, Project Goals: Hidden Valley
  2. 2.0 2.1 Hidden Valley bunker terminal entries; Terminal, Systems Overview
  3. The Courier: "Do you have any other family in the Brotherhood?"
    Veronica Santangelo: "Just my parents, but they haven't been around for a long time. Dad was a Paladin, Mom was a Scribe. They died in the same battle trying to hold off the NCR from... something. I don't remember what it was. Guess it seemed important at the time."
    The Courier: "Who was this Father Elijah to you?"
    Veronica Santangelo: "I would say he was my tutor, but that doesn't cover it. After my parents passed, he looked after me. The whole Brotherhood brought me up, really, but he made sure of it. I never had a grandfather - not that I knew, anyway - but Elijah was in some ways what I'd imagine a grandfather to be."
    (Veronica Santangelo's dialogue) Note: Veronica was born in 2254 and states she was brought up by the Brotherhood, indicating they passed in her early childhood, which pins the earliest known instance of NCR-Brotherhood hostility in the 2250s/2260s range.
  4. The Courier: "One of the few times an Elder was dismissed was due to it."
    Edgar Hardin: "I could be wrong, but I think that's a dead end. McNamara's always followed orders, and we've been incommunicado since fleeing HELIOS."
    (Edgar Hardin's dialogue)
  5. 5.0 5.1 Still in the Dark
  6. Eyesight to the Blind
  7. The Courier: "Where do you want me to start?"
    Robert House: "Since 2278, I've lost five roaming Securitrons near Hidden Valley. I didn't receive any clear video of the incidents, but telemetry from the units destroyed indicates they were attacked with energy weapons. It's obvious that the Brotherhood has a base in Hidden Valley or thereabouts. Finding it won't be easy, but getting inside will be the real trick."
    (Robert House's dialogue)


  1. Fallout: New Vegas Official Game Guide Collector's Edition pp.401-402: "[5.11] Hidden Valley
    Hidden Valley is housed in the remnants of a USAF bunker near the heart of the valley. Abandoned even before the war, the area around the bunker is littered with junk. Signs on the roads and peaks leading into the valley warn that it is a USAF testing range and stretches of drooping wire fences form a pathetic barrier in post-apocalyptic times. Upon entering the outer region of the actual bunkers, surviving Prospectors have reported an eerie feeling, and four bunkers, each with an intercom and complete, almost deafening silence on the other side. Others tell of seeing armored figures exiting the Valley from within a raging sandstorm that seems to arrive every evening and stay for the night. The main entrance is from the south gates, at the end of the side road from Long 95 that passes north of the NCR Correctional Facility [5.15]. There are periodic breaks in the perimeter fence, including a large breach to the north."
    (Fallout: New Vegas Official Game Guide Collector's Edition Tour of the Mojave Wasteland)
  2. Fallout: New Vegas Official Game Guide Collector's Edition p.43: "Brotherhood of Steel
    The Brotherhood of Steel is a militant organization devoted to the preservation of pre-war technology and human knowledge. Their professed mission is to preserve pre-war technology and human knowledge for the benefit of future generations. In practice, its definition of technology is strangely selective, ignoring basic but potentially useful technologies (genetic modification of crops and civil engineering, for example) in favor of combat technology such as energy weapons and power armor: and even now, nearly two centuries after the Great War, the Brotherhood zealously restricts the use and knowledge of such technologies to its own membership.
    The Mojave Brotherhood operated freely amid the Vegas wastes for several years, carrying out many reclamation missions without serious opposition. The balance of power shifted in 2251, when a large contingent of NCR troops entered the region and occupied Hoover Dam. Conflict was inevitable. Nearly two years of guerilla skirmishes culminated in a pitched battle at HELIOS One, a solar energy plant the Brotherhood had been refurbishing for several months with the goals of bringing it back online and activating its hidden offensive capabilities (the ARCHIMEDES II death ray). The battle for HELIOS One (Operation: Sunburst) proved a disaster for the Mojave Brotherhood. More than half its Paladins and Knights were killed. The chapter's leader, Elder Elijah, disappeared without a trace. The Brotherhood was driven from the facility, which suffered extensive damage. Survivors retreated to Hidden Valley. Since that defeat, the chapter's leader, Elder McNamara, has restricted activity outside the bunker to occasional reconnaissance missions and high-value raids. All operations take place at night, and engagement of NCR forces is strictly forbidden. Though the Brotherhood's ascetic lifestyle has prepared its members for a sequestered existence better than most, the passivity of their current situation has proved highly stressful."
    (Fallout: New Vegas Official Game Guide faction profiles)
  3. Megan Parks' portfolio
Hidden Valley