Qin home governs Yuyang county, and the old city is in the southwest of Miyun county in Beijing today. The Great Wall in Historical Records was built by Yan and set up five counties: Valley, Yuyang, Youbeiping, Western Liaoning and Liaodong. Qin Ershi suddenly pushed to defend Yuyang, and Yuyang County of Han family was ruled by the county, and the city was in the fishing water, hence the name. The old city is in the southeast of Liyuan Village, Huairou County, Beijing, and the site is still there. Wang Mang was renamed Tongdao County. The Eastern Han Dynasty was renamed Yuyang County. After the Three Kingdoms Wei Mingdi, all counties were abolished. After the unification of the Western Jin Dynasty, Yuyang County and the former Yangguang County of the Eastern Han Dynasty merged into the Yan State. After Wei moved to the county to govern Yong women (now Wuqing County, Tianjin). The Northern Qi Dynasty ruled Lu County (in today's Beijing). In the third year of Sui Dynasty (583), Huang Kai was abolished.
The great cause of the Sui Dynasty lasted for three years (607 years). Jixian County, Hebei Province, Pinggu County, Beijing and other places, Jizhou in the Tang Dynasty, changed to Yuyang County, and restored to Jizhou, that is, Jingzhao Jixian County (now Jixian County, Tianjin). There is a fishing mountain in the northwest of Jizhou, and the county is in the south of Shannan, so it is called Yuyang.