Why did Gu Changan dig a Qujiang pond in the southeast?

Many people who visit Chang 'an should have been exposed to it. As one of the eight scenic spots in Chang 'an, Qujiang Lake is very beautiful, but even Chang 'an locals rarely know the specific origin of Qujiang Lake. In fact, strictly speaking, Qujiangchi did not appear in the Tang Dynasty, first appeared in the Qin and Han Dynasties, but was later expanded by the Tang Dynasty. Then, why did the Tang people expand Qujiang Pool?

The reason why Qujiang Pool was expanded in Tang Dynasty was mainly from the perspective of geomantic omen. Chang 'an has high terrain in the southeast and low terrain in the northwest, and the gate in the northwest is Tianmen, which is supposed to symbolize imperial power. It should be high ground, so what should I do? You can't waste people's money to find someone to dig and fill it up! There is a saying in the book that the land is smaller than the southeast, the ocean is a pool, the sky is smaller than the northwest, and the stars move to the northwest! So people thought of the way to expand Qujiang pool!

Since ancient times, people have believed in ghosts and gods, and the emperor of the Tang Dynasty chose to expand to Qujiang in the Tang Dynasty for the sake of theocracy and to make the water and soil position of his country's capital more in line with Feng Shui. Of course, this is only the embodiment of ancient superstition. In order to strengthen his rule over the world, he sought a kind of psychological comfort!

On the other hand, the area of Qujiang pond is very large now, with 1000 mu. On one side of Qujiangchi was the royal garden of the Tang Dynasty at that time, and on the other side was the public area of the people all over the world at that time, mainly serving the people. Now it's just a tourist attraction!