What's the secret of Gu Lou? What is the reason why the Old Nine Gates and the Zhang Family are guarding Gu Lou?

The secret guarded by the Old Nine Gates in Tomb Robber Notes is the ultimate secret of immortality after bronze doors. The Zhang family has a big secret, and that is bronze doors. The Zhang family didn't want this secret to spread, and they guarded it for countless centuries. On the other hand, Wang Zanghai wants everyone to know the secret.

Extended data:

The nine grave-robbing families in old Changsha mentioned in Southern School's Tomb-robbing Notes are called Old Nine Doors, also known as Nine Doors Prefect. Old Nine Doors is a prequel to Tomb Robber Notes, which tells the ancestral stories of Wu Xie and others, and tells the daily fragments of their respective characters in a peaceful and short style. It was first published in Super Beauty.

There are nine prefects in old Changsha, and all the other eight lines know it. These grave-robbing families are powerful and involve all aspects of cultural relics smuggling. Almost all the funerary objects inevitably pass through one of them when they flow out of Changsha.

There are different opinions about why it is called the nine-door prefect. The most recognized one is that because there are nine gates in ancient big cities, businessmen entering and leaving the city have to choose one of them, which is what the old nine gates mean. To do business in Changsha, you can only choose one of these nine forces, and there is no other way.

References:

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