Hidden Valley

 is located in what is apparently 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.

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 contain a large entry room with a locked door on the opposite side. 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. The easy door hides a hundred 5mm rounds and twenty four 5.56mm rounds; the average door, a pair of Mini Nukes, a Stimpak, and some 5.56 ammo; and the hard door, 3 ammo boxes, another Mini Nuke and some scrap on the right and a frag grenade and some 5.56 ammo on the left. These items are very hard to see: toggling between Pip-Boy Light on and off helps, and look down to see the items pop up in your display.

One of the three bunkers, has a grenade bouquet hanging from the ceiling at the bottom of the staircase. The entry room contains a sleeping pad, some food, and a journal indicating that someone is using the bunker as a safehouse,

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,It 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 scivvies. 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.

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 and Eyesight to the Blind can be activated 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 without training.

At the shooting range Knight Torres has on her 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, once you got the key, you can get in the shop from the door below, stealing 4 perfect T-45d power armor 3x T-45d power helmet as well a few rifles, and ammo total value of items is 20k caps+

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.

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.

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. (5 hours of gameplay.......lost)