I have Verizon. Just passed the mouth of the canyon, you will lose signal. Up at the lake and or campground it is spotty for texting. Text will come and go here and there. But not a cell signal. I might receive a text while I'm out and about and then I would send my response and just continue my walking and driving around and sometimes it would send in sometimes I would have to resend it.
I don't know about Verizon specifically. But no AT&T or Sprint
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