Cell phones do not work in our area, land line yes, butt-set in a small grab bag with a few other "rare use" essentials if necessary. Flash lights in multiple areas of the home as well as candles, and lanterns. (Might seem odd to some, but remember "mountain" area and suddenly the decor becomes 'functional'.)
Oddly enough 911 does work almost anywhere.
Our daughter and then S-I-L broke down in the desert between mojave and whatever on the 99 going north 2-3am.
End result after dealing with cell co due to issues with emergency response and their lack of reply. I had contacted CHP once our daughter was able to get cell service. CHP said a 911 call works any where AND while only a vehicle issue, they considered any issue in the desert an emergency.
This may only work in CA, however until this thread i have not contacted verizon to see what they say regarding 911. Because well i forgot
I know any cell phone no matter how old and not activated, if there is power, dialing 911 will get you connected to an emergency responder or dispatch person.