What area does Guanzhong refer to?
Guanzhong is close to Qinling Mountains, and Weihe River passes through it, with rich products and outstanding people. There are natural terrain barriers on all sides, which are easy to defend but difficult to attack. Since the Warring States period, there has been a saying of "one country, four blockades". Therefore, in the Han Dynasty, Zhang Liang summed up the advantages of Guanzhong with "a golden city of thousands of miles" and persuaded Liu Bang to make it the capital of Guanzhong.
During the Warring States Period, Zhang Yi told Qin Chen about the plan of "Lian Heng", praising Guanzhong's "fertile land, rich people, numerous chariots, tackling all kinds of difficulties, fertile fields and thousands of miles, and accumulating abundance", saying that "this so-called rich land is also a country under the world", more than half a century earlier than Chengdu Plain was awarded the title of "Land of Abundance". This is because Guanzhong has become a treasure trove of geomantic omen and the capital of emperors since Zheng Guoqu was restored in the Warring States Period.
Extended data:
Chapter 8 of Historical Geography of Shaanxi General History (edited with Shi Nianhai, Xiao and Shaanxi Normal University Press, 1998, March) explains the origin of Guanzhong place names as follows:
Because Guanzhong was not a formal local administrative division at first, there are many explanations. According to Biography of Historical Records and Huo Zhi, Guanzhong is a river, a river from east to east. Wei refers to Weishui (the author should say' drowning' means drowning), Yong refers to Yongshan, River refers to the Yellow River, and Hua refers to Huashan. However, Hanzhong and northern Shaanxi are sometimes included in the Guanzhong area in historical records.
Later, there were some statements, mostly related to arguments. One is between Hangu Pass, Big Three Pass, Five Pass and Small Pass; One is between Hanguguan and Longguan; One said it was between Hangu Pass and Sanguan Pass. There are other sayings. Although these statements came out late, they have roughly the same meaning as the so-called four blockades in the Warring States, Qin and Han Dynasties, and are more in line with the situation at that time.
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