Well, I'm in a bit of a pickle here. Let me explain some background on the community we're trying to help and their problem. That should help.
I'm just going to call the place Clinton, because that's one of the most common names for a town in the US. Can't give away too much about it, but the crux of the problem is that Clinton is very, very secure because of its location. The community is located at the top of a large hill (I can say that because lots of places have those), but in a huge, shallow depression in that hill. Big enough to house hundreds of people and some farmland to boot. Think about some of the river valleys you've seen, or distant plateaus as you've driven down the highway and you'll get an idea of the scope. Clinton is pretty big.
And because it's at the top of that big ass chain of hills, and the hills are covered in trees, and the town itself is basically fifteen feet below where the hilltop should be...well, Clinton is invisible from the road. You could walk around the hills and wouldn't know it was there until you were on it.
The people there do a lot of mining. There's not a lot to be had in the rocks there, but a few natural caverns and a lot of broken rock gives them a ton of extra cool storage space and room to work metal without being seen or heard. Not too far away from Clinton is a cluster of abandoned factories and a good-size town where they regularly search for and gather materials of all kinds. Good number of zombies passing through there, though nothing like the numbers we deal with. The important factors to understand:
The people of Clinton have been creating caches of things in the town to more easily transport them back when needed. They're very careful about not drawing any undead from the town back to the community itself, and because of its location and geography, zombies almost never come across the hidden town in the hills.
The problem is simple. One-word simple. Marauders.
I can write about this now without too much fear that the marauders in question will read this and figure something out. I've been watching them from a distance all morning, and this band of bad guys don't seem to have any mobile communications technology. There aren't any functional cell towers around here, and they don't have a transmitter.
But the marauders definitely do know that people live around here. They've found several supply caches so far and have added them to their own plentiful supplies. More, they've begun a systematic search of the area for the people who left those caches sitting around, correctly guessing that they are recent rather than being left over from before The Fall.
It's pretty clear why I was asked to do this. The marauders have been poking around this area for a few days. Eventually they'll exhaust all the obvious places and start looking at the less likely choices. They'll go into the hills and lead zombies that way, and chances are good they'll find Clinton.
There are no walls to protect these people. They've got weapons and they can fight, having learned the hard way on supply runs into town. But they don't have defenses like we do or a barrier other than the terrain to slow down enemies. Building a wall where they are would be too obvious and noticeable. Leaving their hidden home right now is also too big a risk--what if someone saw them do it? Game over.
They're trapped and in danger and can't do anything about it without exposing themselves. That alone is enough to get me to help. But it's the things they've been making in those caves, out of sight from the world above, that makes the place a vitally important resource we have to save if possible.
But that's another post entirely.