There is actually a village around here where they only have crappy internet.
What they did was get a very fast contract outside and and send it over via directional WiFi, that works basically as far as you can look and there is nothing inbetween that might unterrupt the connection. Theybridge distances of over 20km.
You might try somthing similar. But you have to keep in mind that there has to be nothing inbeetwen, no house, no tree and defenately no high voltage line. And not only in the direct like of sight but also inside the so called fresnel zone.
Also where do you want to place that long cable, unless all that terrain is owned by one if the owners of the houses, those with ownership inbetween would need to acept having a big wire going through their yard.