I find it remarkable how much infrastructure has been dedicated a-pace with progress to the traffic in invisible forces. Of course, not everything out of the past has become obsolete and ought to be gutted or cannibalized for spare parts—even if it has been outmoded.
I bet all those dormant telegraph wires could be revitalized and deputized for a good use too. Though television has taken the high road and almost exclusively is beamed down from beyond the atmosphere, the signal towers have been retrofitted as cellular towers. The principles behind telephony are not terribly advanced, considering that one is just glomming onto an established network. A Funkloch is a German term for the increasingly rare places out in the countryside where there is no cellular coverage—a signal-hole. Though decidedly unaesthetic but I suppose practical since most castles were built in strategic locations, on the high-ground with a commanding vantage, some historic turrets (mostly in private hands, like the tower of Burg Gรถรweinstein near Forchheim) now also host an array of communications equipment. The network of fortifications used to communicate via bonfires and smoke-signals, across the valleys and over considerable distances, and no one could foresee the same ancient brigade bearing our new-fangled wirelessness.