The Great Wall of China had one of those fire towers every some distance (to alert invasions I think), kind of like the set up in the LoTR: The Two Towers. I ne

The Great Wall of China had one of those fire towers every some distance (to alert invasions I think), kind of like the set up in the LoTR: The Two Towers. I never thought people would use these signaling methods to actually transmit these kinds of information. Pretty cool.