A: Here we are on the Great Wall, ladies and gentlemen. It is a landmark which symbolizes China.
B: It must be pretty old. I've heard of Qin Shihuang. Is he the man who had different sections of the walls linked up?
A:That's right. And the Great Wall stretches more than 5 000 kilometers.
B: Walls are usually viewed as a defense project. What are the key parts of the Great Wall?
A: It consists of three parts: the military passes, the walls and the beacon towers. Military passes such as Juyong Pass, the one we are visiting today, are located at important sections of the Great Wall. The beacon towers were used specifically for transmitting military information. Soldiers used smoke in the daytime and fire at night to deliver the message.
B: Lin, I found there are holes both outside and inside the wall.What's their function?
A: They were supposed to drain off water.