You can get a couple of miles out of LoRa. The radios are pretty cheap. Though if your sensor is miles and miles from things maybe a bit of an issue stringing t

You can get a couple of miles out of LoRa. The radios are pretty cheap. Though if your sensor is miles and miles from things maybe a bit of an issue stringing these things out (with solar panels and backup batteries etc) could be a pain. https://hackaday.com/2020/02/26/lora-mesh-network-with-off-the-shelf-hardware/ https://hackaday.com/2020/02/26/lora-mesh-network-with-off-t...