I find it interesting that some folks feel insulted that someone might think cell coverage is less than perfect in some regions of the country. If anyone looks at that Verizon map, for example, it might look like fairly good coverage in most states. But use the zoom function to really look at a state and you will find lots of holes in coverage. In Minnesota, it looks pretty good until you actually zoom in. In many parts of the north, there simply is no coverage. Having just camped at a USFS campground many miles north of Tofte MN, I can attest to the lack of coverage in that area.
Not every place has cell phone coverage, or wifi, or an electrical outlet plug. It is called camping, and I am thankful that such places still exist.
As for the OP, I agree that CB radios, or walkie talkies are probably your best solution.
