《水经注·卷二十八》
扬水又往东北流，东面有赤湖水口，湖的周围五十里，城下的破池，都汇合到这里。
扬水又东北流，东得赤湖水口，湖周五十里，城下陂池，皆来会同。
Yangshui continues to flow to the north east, there is a赤湖 (literally means red lake) water outlet in the east, the lake is 25 kilometers in circumference, the pools in ruins under the city are all connected here.