在中国北方辽阔的原野上,横亘着数道绵延至天边的城墙,那便是著名的中国人土木工程智慧和技术的结晶——万里长城。它东西长6000余千米,有“万里”长城之称。而它的伟大,也并不只是因为工程的艰辛与历史的悠久。根据历史的记载,中国历代一共有20余个王朝和诸侯国参与过长城的修筑工作,而秦代、汉代及明代三代所筑的长城 In the vast northern wilderness of China, there are a few walls stretching to the horizon. That is the crystallization of the wisdom and technology of the famous Chinese civil engineering - the Great Wall. It is more than 6,000 km long, with “Miles,” said the Great Wall. And its great, not only because of the hardships of the project and the long history. According to historical records, a total of more than 20 dynasties and vassal states in Chinese history participated in the construction work of the Great Wall. The Great Wall built by the Qin, Han and Ming dynasties