National Guard Depot

Located along the northern edge of Downtown DC, the National Guard Depot is a high-security compound that used to be the headquarters for the Washington militia. It can be reached from the Wasteland, avoiding the Metro system. An easy way to find the Armory, is to head directly south from Vault 108, or from the Robot Repair Center (which is directly north of Vault 108). One can also head east from Friendship Heights along the wall of buildings, past Rock Creek Caverns.

National Guard Armory
The Armory is only accessible after traversing the National Guard Depot, the National Guard Training Wing, the National Guard Depot Offices, then exiting from the Offices back to the National Guard Depot (update - you can also reach the switch from jumping on a slope in the mid level of the room). Just as you exit back into the Depot, there is an electrical switch about 15 feet to your left. This will unlock the Utility Door two stories below you, which in turn allows you to enter the Armory. (The utility door cannot be lockpicked, even though it is shown with a Very Hard lock). BUT, be careful, there is a Sentry robot or a Mister Gutsy right inside. Activating the second switch inside the utility room will open a trap door that leads into the Armory itself.

National Guard Bunker
The National Guard Bunker, accessed through the National Guard Armory, is opened by completing the unmarked quest Keller Family Refuge. Inside the bunker is the Experimental MIRV (and a plasma grenade hidden in a cooking pot on the first set of shelves left-hand side.) Also 5 Mini Nukes can be found next to the MIRV and a Nuka-Cola Quantum lies in a bin near the back. You may also come across a Glowing One inside.

Inhabitants
The National Guard Depot is mainly inhabited by Sentry Bots, Mister Gutsys, Protectrons, Robobrains and Turrets.

Depot

 * Nikola Tesla And You located in the National Guard Depot, in a storeroom on the lowest level (If you stand in front of the "Very Hard" door leading to the armory it is the storeroom directly to your right in one of the shelves.)
 * Pre-War Book: two located in the National Guard Depot on the third floor, up the staircase to the left after entering from The Capital Wasteland, reachable by jumping over the shelves and pipe at the top of the stairs. The books are on the top shelf of the shelves against the left (Eastern) wall. There is another set of stairs leading to them against the South wall, in the South-Eastern corner of the room.

Training Wing

 * Go up the eastern staircase and follow the hallway to the only room up there. As you enter there is a standard metal/grey desk directly in front of you with a Tales of a Junktown Jerky Vendor on it.
 * There is a safe in a adjacent room near where you found Tales of a Junktown Jerky Vendor. You walk through a collapsed section of wall from this room to the room with the Average Locked safe.
 * Safe may contain a Stealth Boy.
 * Pre-War Book on the shelf above the above mentioned safe.
 * Random weapon along with ammo. Found in one of the 2 wooden gun cabinets in the same room as the 2 books above (Pre-War Book and Tales of a Junktown Jerky Vendor).
 * About 4 Combat Helmet and 6 10mm SMGs and 6 Assault Rifles in the room after the hallway with the patrolling Sentry Bot, right before the locker room leading to the shooting range. The weapons and helmets are in the wooden shelves behind the counter with 2 non-working terminals.
 * A Sniper Rifle and some .308 ammo in an ammo box are located in the shooting range.

Offices

 * Duck and Cover! located on a long counter in an irradiated section of the National Guard Offices portion.
 * Three more Pre-War Books in the National Guard Offices on the shelves in the center of an open collapsed two floor room, one level above the long counter in an irradiated section as mentioned above.

Armory Storage

 * The Bobblehead: Small Guns located on a shelf in the sealed storage room in the basement of the Armory.
 * Four Assault Rifles and 28 5.56mm Round ammunition.
 * Missile Launcher and 10 Missiles.
 * A Minigun and 206 5mm Round ammunition.
 * Two 10mm SMG's, two 10mm Pistols and 84 10mm Ammo.
 * 4 Rad-X's, 3 RadAways, 4 Stimpacks, 2 Buffouts.
 * 9 Purified Water.
 * 4 Pulse Grenades and 4 Pulse Mines.
 * 2 Combat Armors and 4 Combat Helmets.
 * 2 Radiation Suits.

Armory Bunker

 * Five Mini Nukes and the unique Fat Man, the Experimental MIRV.
 * A Nuka-Cola Quantum (underneath the table that holds the Experimental MIRV).
 * 1 Purified Water.
 * A copy of U.S. Army: 30 Handy Flamethrower Recipes (on the same table as the Experimental MIRV)
 * All of the ingredients for a Nuka Grenade are located in the bunker (Nuka-Cola Quantum, Tin Can, Abraxo Cleaner and Turpentine) so using the Workbench the player can craft one; should they have the schematics.
 * A Plasma Grenade in a large pot (non-item so it will have to be shot / pulled off with the "hold" function),on a shelf (next to one of the two First Aid Box's); the player.
 * 5 Pre-war Moneys
 * 107 darts (100 in boxes, 7 in a container)

Outside

 * Four ammo cases in a military truck in the parking lot (though you may have to use one of the spare barrels from one of the other trucks to get in the back of the truck)
 * Nuka Cola machine right outside the entrance
 * A patrol of Brotherhood Outcasts will spawn outside of the fort next to the trucks outside of the parking lot
 * To the north of the armory, amongst the destroyed houses is what appears to be a single 10mm pistol lying next to a burnt skeleton. However, it is actually a stack of 7 identical 10mm pistols. The house containing these pistols is first house north-east of the playground area.
 * If you head due west from the Depot entrance, staying on the road heading downhill, as you reach the intersection just south of the Rock Creek Caverns (a very brief walk from the Depot), you may be ambushed by Super Mutants and Raiders, possibly depending on your level.

Glitches

 * You can get inside the bunker without getting the transcripts. To do so, walk into the corner made by the door and bunker access terminal. Then crouch, go into third person view, and twirl the camera around until it says "activate electrical switch". The trigger is very small, but should appear on the door or the door frame, a little higher than the player's head. Activate it, and the bunker door will open. This is a brilliant time saving method and should be used if you don't want to bother hunting down the transcripts. (Confirmed on PS3, PC and 360)
 * A character with high Agility can enter the Armory without going through the Training Wing and Depot Offices. Locate the staircase in the middle of the eastern wall of the National Guard Depot, and climb to the top. From there, head due west past the fallen steel truss, around or over the gap in the floor, and go through the open doorway. Straight ahead is a pile of fallen floors or walls blocking another staircase. By jumping up the left side of this rubble (place a barrel to jump on) and then crouching, it's possible to climb the rubble and stairs to gain access the the highest level of the building. From there, head to the far southeast corner where you can jump down to the electrical switch to the Armory. (Confirmed)
 * You can get to the higher level of the top floor by stacking barrels. However, it's very hard to do (you need at least 5 barrels) and there's nothing up there but an empty suitcase and an open safe, unless you want to just jump off the top which teleports you to the 4th floor.
 * There is another way to get up using only one barrel at the northwestern end of the second floor down, push a barrel to the top of the ramp, and jump to the top.
 * There is a way to get to the top of the National Guard Depot building by only having to use two barrels. The player has to go to the middle of the fourth floor then go to the fallen radio tower and the caved in ceiling. From there the player has to put a barrel on the radio tower and jump on it from the collapsed ceiling, putting the player on the fifth floor. The player then has to go to the inaccessible stair case with the emergency lights. Put a barrel on the patch of rubble by the collapsed cubicle. Jump on the tallest corner of the collapsed cubicle, then jump on the barrel and then to the top floor.

Appearances
appears only in Fallout 3.

YouTube Videos
A faster way to open the Armory door (instead of using a barrel you can jump on dogmeat) WWf2XelJzOs


 * Getting inside the bunker without the transcripts

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