Yuandadu is the largest newly-built city in China since the Tang Dynasty, and Beijing was rebuilt and expanded on the basis of Yuandadu in Ming and Qing Dynasties. 12 14, the Mongolian army forced the Jin Dynasty to move its capital from Zhongdu (now Beijing) to Kaifeng. The following year, Genghis Khan resumed his old name-Yanjing. After Kublai Khan proclaimed himself emperor, he changed Yanjing to Zhongdu, and began to build a new capital in the northeast of Zhongdu in 1267, calling it Dadu. The plane of Dadoucheng is rectangular with a circumference of 28,600 meters. The south wall is slightly south of Chang 'an Street, the east and west of Beijing, and the north wall is now Beitucheng. The east-west wall coincides with the east-west wall of Beijing in Ming and Qing Dynasties. There are 1 1 gates in the city, of which Heyimen and Heping Zemen are the later Xizhimen and Fuchengmen; Chongren Gate and Qihuamen were later Dongzhimen and Chaoyangmen; Other names, such as Anzhen Gate and Guangxi Gate, have been used to this day.

The imperial city is in the center of the south of Dadoucheng, including Miyagi and Taiyichi (now Beihai, Zhonghai and Nanhai) and Long Live Mountain (Qiongdao in Beihai). The south gate of the imperial city is called Li Zhengmen, which is in today's square. The layout of Dadoucheng was designed according to the principles set by Zhou Li, and most of the names of gates and palaces came from Zhou Li. The street layout of Dadoucheng is very regular, all in four directions: east, west, north and south. Some alleys are called hutongs, and this name has been passed down to this day. The completion of the capital of Yuan Dynasty is a milestone in the history of urban construction in China. It is the last capital of China feudal society built on the ground according to the overall planning in advance, and it is also one of the most magnificent cities in the world from13rd century to14th century.

In May of the 28th year of Zhiyuan (129 1), Kublai Khan ordered the suspension of Shangshu province, and the provinces below the right prime minister were changed to Zhongshu province, and its Shangshu province was changed to Zhongshu province, referred to as Shu Hang province. Provincial system, that is, the central government has a Chinese book province, the prime minister is in charge of state affairs, the Privy Council is in charge of military affairs, and the Yushitai is responsible for supervision; Set up provincial books (provincial books) in the local area. Each province has a prime minister who is responsible for the military and political affairs of the province. There are provinces, prefectures, prefectures and counties. The Yuan Dynasty established 1 1 provinces in China, namely Lingbei, Liaoyang, Henan, Shaanxi, Sichuan, Gansu, Yunnan, Jiangsu, Zhejiang, Jiangxi, Huguang and Zhengdong. As for Shandong, Shanxi, Hebei and Inner Mongolia, they are called abdomen areas. As a central special zone, it is directly under the jurisdiction of Zhongshu Province. The establishment of the provincial system politically consolidated national unity and ensured the centralization of the administrative system. This is a major change in the history of China's political system, which has a great influence on later generations.