There were only two emperors before the Qing dynasty entered the customs. What does it mean to enter the customs, and how to divide the customs inside and outside?

In the Qing dynasty, Shanhaiguan was used as the dividing line to divide the internal and external customs.

The division of customs inside and outside the customs in Qing dynasty;

1. During the Ming and Qing Dynasties, the area west of Shanhaiguan was called "inside Shanhaiguan", and the three northeastern provinces, namely Liaoning, Jilin and Heilongjiang, were called "outside Shanhaiguan", which was named after being located outside Shanhaiguan.

2. In Shanhaiguan, the ancient dynasty with its capital in today's Shaanxi Province is usually called Hanguguan or near Wang Ji, west of Tongguan. This refers to the area west of Shanhaiguan or east of Jiayuguan.

3. Outside Shanhaiguan, it refers to the area east of Shanhaiguan or west of Jiayuguan or north of Juyongguan.

Extended data:

Shanhaiguan, also known as Guan Yu, Guan Yu and Lu Linguan, is located in the northeast of Qinhuangdao City, Hebei Province 15km, and is one of the northeast passes of the Great Wall of Ming Dynasty. Before 1990, it was considered as the starting point of the eastern end of the Great Wall in Ming Dynasty, and it was also known as the "Three Wonders" of the Great Wall in China (Shanhaiguan in the east, Zhenbeitai in the middle and Jiayuguan in the west).

In the 14th year of Hongwu in Ming Dynasty (138 1 year), the city was built, the customs were built and the guards were set up, so it was named Shanhaiguan. Shanhaiguan city is about 4 kilometers in circumference, connected with the Great Wall and taking the city as the gateway. The city is 14 meters high and 7 meters thick, with four main doors and various defensive buildings. Including "the first pass in the world" Arrow Tower, Jingbian Tower, Muying Tower, Lulin Tower, Wengcheng and 1350-meter-long Great Wall of the Ming Dynasty Plain.

References:

Shanhaiguan Baidu encyclopedia