I’ve been to Alaska twice (unfortunately one of those times was very early spring). Anchorage and Fairbanks, I’m guessing the two biggest cities. In either city, it doesn’t take much driving time to be in the middle of absolutely! nowhere. Alaska is one of those places the satellite SOS feature was made for.
The SOS feature is a brilliant addition to the iPhone. I doubt I would ever be out in the wilderness in the wee hours, but for those who are, I think it's essential!