C439 Pharmacist guo's suspicion

The Yan Shan Prefecture was a broad geographical name that governed twelve counties. It covered the later generations of Wangping City, Changping, Liangxiang, Yuhe, and other counties.

As the Nanjing of Liao, the important town of Song, Yan Shan Prefecture was one of the top cities in the north of Song Dynasty, the walls of which were over ten meters high, and the jade belt river encircled them