A few years ago, I was visiting Tripoli, Lebanon. Tripoli (pronounced "trablous" in Lebanese) is a dense forest of decaying, shoddily constructed buildings and roads. Several days into my trip, it occurred to me that there wasn't any clear infrastructure in the city for distributing cables or telephone lines. Everything seemed haphazardly put up.
I asked my hosts how they got their internet connection set up. They said that they didn't have the modem, but someone in a nearby building did. Confused, I asked how they were physically connected to one another. They said that the owner of the modem tied a rock to the end of a very long ethernet cable and tossed it to them from their balcony.
A few days later, there was heavy shelling and several rockets hit the building we were staying in. Parts of the building were destroyed, and there were even holes left by snipers in our balcony door. However, the internet connection never dropped during the period of unrest (except during the scheduled power outages).
While it seemed sketchy at first, it turned out to be surprisingly robust.