Re: 5G? what about the back hauL?
Optical fiber is the obvious way but also expensive. It would involve a LOT of digging. You could also return to the lily pad net idea mentioned years and years ago and deploy base stations in e.g. every lamp post. These already have cabling facilities, with luck you can pull more fiber through the cable sleeves and into the base station..
Since fog cuts into the bandwidth you can use free space optical links. Fog will reduce back haul efficiency but that is not a problem when handset bandwidth is reduced anyway.