Verizon has mobile internet service that will work while you drive down the road as long as you have 12v power for it. We used to have a router and their service and had data service with that in places that verizon cell phones did not work. The coverage area is not the same for stand alone data service as with a phone/hotspot. We now have a device thru ATT that is no longer available and have had great coverage with it. Also mobile. They probably have something available. The drawback is the cost if you use a lot of data. Most private campground at least have an area that picks up service but many also have great service.
