The location appears to have been occupied by trappers before being overrun by feral ghouls. However, there is still a working turret outside of the tunnel, presumably set up by the trappers.
There is an open gate within a barricade across a small gulch, with one working turret. Inside the west wall of the gulch is the entrance to the tunnel which takes you south to Pine Crest Cavern.
There are three ways to enter the cavern: a one-way entrance from the Pine Crest Cavern that allows the player to fall through a tunnel and roots into a pond of water, the two-way entrance from the former trapper camp in Kitteredge Pass and a hidden opening a bit west of the Kitteredge Pass. This last entry is hidden behind a bush on the side of a hill, it is most likely where the ghouls came through.
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