At the beginning of 20 10, Beiling of Caijiafen Village was identified as a commercial site by the third cultural relics survey in Hebei Province. Later, after many local researches, it was found that Beiling was also called "isolated city", and a large number of bronzes, pottery and stone tools were unearthed. In addition, Caijiafen is located in the south of the county 12, near Xuanshui (qinglong river) and Sui.