Deathclaw Sanctuary

Deathclaw Sanctuary: Located in the Northwestern region of the map, South - South-West of Fort Constantine, South of SatCom Array NW-05a, between Dickerson Tabernacle Chapel and Broadcast Tower KB5.

Tips

 * If you're not a fan of them jumping at you, make a dart gun to cripple their legs
 * Fortunately, the tunnels are ideally suited for stealth play, allowing patient explorers to retrieve Vengeance without engaging any of the Deathclaws. If you have downloaded the new DLC pack (Operation: Anchorage) and completed it, the Chinese Stealth Suit you get is a big help and preserves stealth boys. Alternatively, most (all?) of the Deathclaws follow paths through some of the narrow tunnels, so it's also an excellent place to combine stealth with mines. You can find a good two dozen Frag Mines on the bodies scattered around (the exact number may be somewhat random), but bring your own Bottlecap Mines for quicker results.
 * The combination of sneaking around the cave while using the Alien Blaster usually results in one hit kills on the Deathclaws.
 * If you're having a hard time seeing in the darkness, adjust your brightness. This will let you clearly see everything, and won't give away your position like the Pip-Boy flashlight does.
 * When engaging or alerting a Deathclaw it's best to put your back to the wall and fight, this serves a dual purpose, it keeps the player from backing into additional Deathclaws, and it's safer (attacks from behind are part of Deathclaw A.I.).
 * If you have found Dogmeat already, have him wait at Vault 101 whenever you are going to a Deathclaw infested location (such as the Deathclaw Sanctuary or Old Olney) as Dogmeat will intercept incoming Deathclaw and try to engage them in close combat. Three or four hits from a Deathclaw is all it takes to kill Dogmeat. Alternately you can have Dogmeat wait just inside the Deathclaw Sanctuary entrance, and while you clear it out he will stay out of combat.
 * Unless you are trying to sneak while looting all the bodies and avoiding the Deathclaws, it is best to bring a follower to watch your back such as Fawkes.

Notable Loot

 * There is a locked footlocker right outside the cave entrance which contains various guns, ammunition, stimpacks, and a Duck and Cover! book. There is likely to be a Deathclaw outside the entrance, too.
 * Bobblehead: Endurance directly south of the entry inside the cave, in the first large chamber - on a short pedestal near a pile of corpses and a Rotting Brahmin. (It is to the immediate left at the bottom of the entry slope, ground level) Also in the first chamber:
 * A Mini Nuke
 * A Nuka Cola Quantum - East side of the chamber, on the ground; look for the glow.
 * A Nikola Tesla and You
 * Vengeance in the far southeast of the caves
 * Jack (Depends on main quest timeline)
 * A fairly rare Roving Trader Hat (+5 to Barter) among the second pile of bodies in the second large chamber in the cavern, east of the entry, straight through a T-junction corridor.
 * There's an Enclave soldier that randomly spawns in the cave wearing Tesla Armor, if you haven't cleared the sanctuary beforehand this soldier may be found dead (preyed upon by Deathclaws).
 * There are about seven heaps of corpses and body parts scattered through the cave. Each heap has 2-3 lootable corpses. A couple of the corpses are traveling merchants who have the Trader Hat and Outfit, about 200 caps, and a fair amount of other mediocre stuff.