Hidden Valley

 is located in an abandoned military establishment. It is a fenced-in area nestled between hills and rocks, the main access being via a road near Sloan and additional access at the northwest and southeast corners where the fence is down. Additionally, there are small side-paths, at least one of which is heavily inhabited by bark scorpions and the occasional Giant Radscorpion when going in the direction of Scorpion Gulch nearby.

Inside the fenced area are 4 old underground bunkers, three of which are caved in beyond the initial room and the fourth of which has been renovated by the Brotherhood of Steel as a place to hide from the NCR.

During the night, vicious man-made sand storms rage around the bunkers - defense mechanisms the Brotherhood uses to hide their bunker from electronic surveillance, detection, or targeting. The sand has metallic particles mixed in and the sand storms are caused by electric fans.

It is one of the few places the BOS can hide, when they lost the war with the NCR. So now they are mainly recluses. Like in the first two Fallout games, most BOS soldiers are wearing t-51b power armor instead of t-45d power armor. Most of the inhabitants are on-edge since their defeat at the power station HELIOS 1, and are upset because they are not allowed to leave the bunker.

It is not recommended to charge in guns blazing; many of the troops in the bunker have high-level weapons such as the gauss rifles as well as high damage threshold due to their armor.

Layout
The four bunkers are spread around the perimeter of the area. A hollowed-out rock with a little ammo in it (and a heart painted on it) is in the central area.

Three of the bunkers each contain a large entry room with a locked door on the opposite side. The area beyond the locked door is blocked by rubble where the bunker has caved in, but it is possible to step into the rubble and search for loot. The locked doors are of varying difficulty.

East Bunker The entry room has 3 skeleton's with a bottle of wine on a sleeping mat. The locked (Easy) door in this bunker hides a hundred 5mm rounds and twenty four 5.56mm rounds. North Bunker This entry room has a wooden-crated yellow barrel holder on the left and large metal storage containers on the right. The locked (Average) door are a pair of Mini Nukes, a Stimpak, and some 5.56 ammo. South Bunker This bunker has a grenade bouquet hanging from the ceiling at the bottom of the staircase. The entry room contains a sleeping pad and a sack, along with a journal indicating that someone is using the bunker as a safehouse. The locked (Hard) door here opens the way to 3 ammunition boxes, a Mini Nuke under a Tin plate which you will have to move in order to see, a steam gauge assembly and 2 units of scrap metal on the right, and a frag grenade and some 5.56 ammo on the left. After the Brotherhood of Steel Quest to rid this bunker of it's inhabitant, you can find 3 boxes of 15 .308 shells on a shelf on the left along with about a dozen food supplies.

The items beyond the locked doors are generally hard to see; toggling between Pip-Boy Light on and off helps. Look down to see the items pop up in your display.

West Bunker

The fourth bunker, on the west side of the area, is home to the Brotherhood of Steel. The bunker is marked by a small broken tree stump directly on top of the dome.

Player Interaction
WARNING! Going into the BoS bunker wearing any type of NCR armor will make the paladins immediately hostile!

Note: If you have discovered the two dead Brotherhood of Steel Paladins at the REPCONN Headquarters (on the third floor) or the one near Black Mountain or the 2 dead Brotherhood soldiers in a ditch on the artillery battered area outside Nellis Air Force Base and took the note they were carrying, you can say the password to the intercom of the facility with the Very Hard lock or by having follower Veronica Santangelo with you. You can also gain access through the quest Wild Card: Side Bets.

(SAVE FIRST, the game may glitch and not give you your guns back before this "test".)

After entering a couple of doors, you will be greeted by BoS Paladins who will demand that give up everything you are carrying, right down to your underwear. An explosive collar is placed upon the Courier's neck to insure that you do not leave the area before completing a quest given to test you. All of your gear is returned just before you exit the bunker to complete the test, but the only way to get rid of the collar (and retain your head) is to complete the test or by telling the NCR ranger about it.

Once you pass the test, the collar is removed and you are given the run of the bunker system. (NOTE: If for any reason you try to go back before completing the test and you hack the Very Hard door lock, the BoS will attack you when you enter, even if you complete the test before entering.)

Related Quests
The quests: Still in the Dark, Tend to Your Business, For the Republic, Part 1, For the Republic, Part 2 and Eyesight to the Blind can be activated and are finished here.

Notable loot
If you are looking for a free set of the Brotherhood's armor, one of the three rooms right next to the elder's room contains a set of old T-45d power armor (with helmet) along with a Super Sledge, plasma rifle, and plasma pistol. These are illegal to take and the armor cannot be worn by the courier without training. The armor you steal in Hidden Valley is not faction-specific, though (as opposed to armor found on dead BoS soldiers), and most permanent humanoid companions can wear it by default.

Knight Torres, at the shooting range, has the key for the door that is on the sub level of the shop-counter. Use a Stealth Boy to pickpocket the key, as you cannot get behind her. With the key, you can access the shop from the door below, stealing four perfect sets of T-45d power armor and three T-45d power helmets, as well a few rifles and ammo; the total value of these items is over 20,000 caps.

In the shooting range outside the quartermaster's office it is possible to find two gauss rifles lying on the ground in the left-most partition.

In the white plastic bin by the desk in Schuler's office. Bunker L1, west of the central hub corridor junction a Nikola Tesla and You can be found.

Appearances
appears in Fallout: New Vegas.

Bugs

 * When you are in the BoS Bunker you can help Scribe Ibsen isolate a virus in the database. It is possible that using the Science check causes a glitch that leaves you unable to finish the task.  Make sure to talk to Ibsen any time the virus jumps and you should be fine.


 * In some cases. entering and walking down the stairs, after you get disarmed can cause crash to desktop repeatedly. This happens when wearing the rebreather, remove it before entering the bunker.


 * It is possible to become trapped after starting the quest Still in the Dark. Despite instructions from the elder to perform a task outside the bunker, the door to leave is locked and needs a key.  This was solved by pickpocketing a key from the head of security.


 * When using the 3 BoS leader's key cards, the password authorization terminal for the self destruct sequence sometimes will not work properly and freeze.


 * At the start of Still in the Dark, Elder McNamara may stop dead in his tracks in the main hall (with the BoS banner in-between the two laser turrets) if you step outside whilst he's on his way to the command room.


 * You can also get unlimited energy weapons ammo if you just go out and inside the base as many times as you want and making sure you check the black box containing the ammo each time your in the bunker, the ammo varies from micro-fusion cells, energy cells, or electron charge pack


 * If you have the emergency NCR radio exiting the bunker will sometimes cause a NCR trooper to appear.


 * Upon setting the base to self-destruct, sometimes when you use the scope on any scoped weapon, no matter what it is, you will get a Terminal screen that doesn't pause the game when you do so.


 * In the hill paths leading to Hidden Valley, it is possible to encounter deathclaws from Quarry Junction, including the dreaded Deathclaw alpha. It may pop out from under the hills or rocks.


 * The paladin sitting at the shooting range may go missing. His reference ID is: 0010A6FF - use the console command "prid 0010A6FF" followed by "moveto player" He then returns WITH his helmet on, wonder what he's been up to ??


 * Xbox 360 Users may not get their guns returned during the first encounter test, save before entering and meeting the Brotherhood for the first time.


 * Sometimes when saying the pass word the BoS just come out and attempt to kill you (wrong appearence only)


 * In the South bunker if you activate the tripwire (which is attached to the grenades), it may kill you and freeze the game/console (PS3, others?)