The Camp Guardian caves is a large network of tunnels and a few large open areas, with its main entrance being at Camp Guardian Peak, directly north of the tent. There are also two additional exits toward the southern end of the cave. The first comes out on a ledge over top of the pathway you took up, just past the Camp Guardian sign. The second is located in an underwater passage at the southern most point of the cave and comes out in Lake Mead, a short walk south of the Camp Guardian sign. The cave is inhabited with 15 to 20 lakelurks and a lakelurk king.
Following the passages will lead you to the injured Private Halford. With a high enough Medicine skill (50) or a doctor's bag, the Courier can heal the Private at which point you can either tell him the path is clear to leave, which unless true will result in his certain death, or you may ask that he help you clear the caves of the remaining lakelurks with a speech check (50). Note: Though the pathway that you took to reach him is clear and the quickest way out, he will not take this route to leave, but rather he will head even deeper into the cave.
If you approach either entrance to the caves, Halford will leave the party stating that he is close enough to the entrance to get out himself. The largest number of lakelurks are found in the area with the King, egg clutches, and the 11 dead NCR Troopers as well as a dead caravan brahmin. Connected to this room is a mostly flooded chamber containing 1-2 lakelurks. At the far end of this chamber is a flooded passage that exits into the Colorado River.
There are two locations with similar names. The first, a much smaller cave, located on your way up to Camp Guardian Peak containing giant rats, is called "Camp Guardian cave". While this location is named "Camp Guardian Caves."
There are numerous items dropped down on the ground, from hunting rifle to service rifle. It's very hard to see them in the gloom of the dark caves. Rex's Search and Mark will illuminate them and make collecting much easier.
pcxbox360 Sometimes if you do not help the injured soldier (Private Halford) before exploring the rest of the cave, when you come back the option to help him is no longer part of the dialogue.[verified]
pcxbox360ps3 The entrance section of Camp Guardian Caves may be pitch black even with Cateye. Once you walk further in this will correct itself. However it sometimes may continue to bug and walking further into the cave will not help, and it will not light up at all. It will also randomly turn pitch black while inside the cave.[verified]
ps3 Upon exiting the lower cave, ED-E may appear in Black Rock Cavern. Fast traveling or entering a load screen will return him to you.[verified]
xbox360ps3 Sometimes when fast traveling away from Camp Guardian, the screen will become very blurry and dark and can make the game virtually un-playable. One way to fix this is to fast travel back to Camp Guardian, then to Lake Mead caves, enter the caves and then exit and it should fix the problem. Taking a Cateye is also effective, and the issue will resolve by the time the drug's effect has faded.[verified]
xbox360ps3 Upon exiting the cave from the underwater pool that the Private runs through, all relations with NCR, Khans, Fiends, and Legion may be reset.[verified]
pcxbox360ps3 When leaving the Caves via the underwater exit, if you still have Halford following you he will get stuck on the roof of the exit tunnel, swimming forever and you will not get Private Halfords Note to make the dog tag fist.[verified]
xbox360ps3 If Private Halford is asked to support you in killing the lakelurks and you exit through the mid level exit, then he will continue to follow you for all eternity. When spoken to he believes he is still in the cave and asks you to remain quiet. He will kill any enemies that approach or are nearby, just as a companion would.[verified]