The Sui Dynasty carried out political reforms, and established for the first time the bureaucracy of three departments and six ministries. The Sui Dynasty also initiated the policy of selecting officials through imperial examinations. The central government had the official patronage. In military system, the administration of servicemen's household registration was formerly separated from that of civilians, and now the administration of both servicemen's household registration and their fields were transferred to the region and county. And the former three-level local administrative system of region, commandery and county was simplified to two levels of region / commandery and county. A series of new policies were adopted to strengthen the centralization of state power. For the sake of grain transportation by waterways to the capital and also for military aims, Emperor Yang of the Sui Dynasty had the Tongji Trench, the Han Canal, the Yongji Trench, the Jiangnan River excavated successively from the year 605 to 610 AD. This was the well-known Great Imperial Canal connecting five water systems including the Hai River, the Yellow River, the Huai River, the Yangtze River and the Qiantang River. It started north from Beijing and reached Hangzhou in the south with a total length of more than two thousand kilometers, serving as the main artery of transportation from south to north of China. It turned out to be the largest irrigation project at that time in the world.Youzhou under the Rule of the Tang Dynasty.

After several hundred years' convulsion and division, the Sui Dynasty unified China anew, and the unification lasted till the end of the Tang Dynasty. The following hundreds of years of development pushed Chinese feudal society to the peak of flourish and prosperity. Youzhou was still a city of military importance and an economical and cultural center in the north in the Tang Dynasty.

The scale of Youzhou (Ji city) in the Tang Dynasty, according to Geographical Records Composed in the Taiping Reign which quoted from Records of Commanderies and Princedoms, was recorded: The city Ji is 4.9 kilometers from north to south, 3.5 kilometers from east to west, and has ten city gates altogether. Therefore the whole town had the perimeter of 11.5 kilometers in the shape of a square. The exact location of the town failed the historical books. According to the information drawn from the unearthed epitaphs and stone inscriptions of the Tang Dynasty and the Tang combined with the materials resulted from the field research, quite a few aspects could be confirmed about the city location, its lanes ,alleys and suburbs.