What's the special meaning of 49?

"April 9" means entering the cold weather from winter to the future, and the fourth nine days are called "April 9". Enter "No.9" from the date of winter solstice. "Counting Nine" is a folk solar term in winter in China. ?

From winter solstice to Sunday, it is called "Jiujiu", every nine days, the first nine days, the last nine days, and so on, until the ninth nine days, the number reaches 998 1 day.

Since the Ming Dynasty, Beijing has formed an architectural pattern of "nine miles away, seven miles away from the imperial city and four miles away". "There are nine gates in the inner city of Beijing, seven gates in the outer city and four gates in the imperial city". The inner, outer and imperial cities are divided into five administrative regions: east, west, south, north and middle. The rulers of the Qing Dynasty carried out the policy of ethnic discrimination and drove all Han people to live in other cities.

Make room for the Eight Banners Army and their families in the inner city (until the middle and late period, only senior Han officials were specially rewarded to live in the inner city, such as Liu and his father Liu Tongxun). In this way, a Beijing city has been artificially divided into two parts, the inner city has become a military garrison area and a family area, and the outer city is a simple residential area. The inner and outer cities are distinct, and the boundaries between the flag and the people are strict.

At that time, the Eight Banners were very proud of their privileged position and called their residence "Four Nine Cities". To show that they are a special group, guarding the Forbidden City and above others, so as to distinguish people living in outer cities. ?

Beijing is called "Four Nine Cities" because Beijing was divided into ten urban areas in the Qing Dynasty. Of course, the Forbidden City (also an urban area) is a forbidden place for ordinary people, so people in the Qing Dynasty called Beijing the "Nine Cities".