In deep Southeast Texas many of the ranchers still use the ranch radiophone system I set up four decades ago when I owned a GE Service Station (South Texas Radio Service). They are all too far away from any landline service, and even to this day cellular service just doesn't exist outside of major towns and along major highways (of which there aren't that many). The subscribers were overjoyed when I finally did away with the operator assistance and automated the system.
They could optionally equip their vehicles with mobile units for unit-to-unit contact, as well as the phone service. Eventually King Ranch contracted with my company to install a five channel trunked system for their extensive ranch, with a tower a few miles south of Kingsville and another just south of the Armstrong Ranch to extend coverage to their extended ranch holdings. It too offered both dispatch radio and phone service.