So I spend many, many hours scraping, saluaging, and building a defensive wall around a settlement. (kicks butt if I do say so myself)

and then I get a message settle under attack, and i find the bad guys INSIDE the fences, using melee against my settlers, and having completely bypassed my multiple level wall (foundation blocks) turrets, and guard posts.

WTF?

if they can just sneak in and cause this kind of havoc, why build fences, walls and turrets?

Thanks for reading.

QM

Fences are for show. The defense number is what's important. I think that's right anyway.

Place more defenses I would suggest.

Hi Quasimodem,

For once as jasper1979 says is partly correct: The original cause of an attack is for most parts related to your defense value. If you put 20 turrents into a shed without any door, your settlement will be attacked less frequently.

As far as I know, there is no "zero" chance.

There are two "modes" of an attack: one you re partifipating in and two those attacks you do not participate. I am not completely sure how the chances of a success are determined if you are not participating (I had times were a perfectly defended settlement were overrun while I was not around).

About fences: They are not entirely for show. You have to know where enemies spawn. The very best example is Somerville Place. I had the whole place fortified and two times super mutants seemed to spawn right next to the central house.

In this case, no fortification helps whatsoever.

If you are present when a attack starts (e.g. Sanctuary), enemies will spawn outside of the perimeter. In those cases it helps to have a light fortification.

After my forth or so play-through (each time at least until level 40) I do not advise to really build a wall around your settlements. While it looks awesome, you will soon lack material (which you need to purchase after scraping every tree).

Of course how you fortify is a bit dependent of your play-style. I tend to setup watchtowers within "sight" to each other (e.g. in Sanctuary I fill out the gapes in the hedges with Watch posts).

As I learned some weeks ago, if you setup sirens (Resources -> Misc), these are operated by nearby settlers in case of an attack (including switching them off afterwards).

One final hints regarding turrets: While AI seems not very strong in FO4, attackers will primarily shot down generators. If your whole base consists of electrified turrets you will sometimes lack defenses if generators are "just covering the needs".

The fence around sanctuary helps. I have enemies spawn outside the fence ...

Each settlement has set spawn locations. If you can figure out where those spawn locations are, then you can effectively wall off your settlement. The problem is several settlements have spawn points near buildings or close-ish to the center of the settlement. So it's up to you to find these spawn points then wall them out. For example, Sanctuary has four spawn points - one is at the end of the cul-de-sac, one is the bridge from Vault 111, one is from behind the last house north of the walking bridge from Concord, and one is from the hills south of the river. If you wall off accordingly, you can keep out the spawns.