《水经注·卷二十七》
汉水又往东流，右岸有大势，因有急流阻隔，所以又称为急势。
汉水又东，右得大势，势阻急溪，故亦曰急势也。
Here a small city is built based on the mountain, within 2 miles, under the jurisdiction of Liang Zhou supervisory inspector Ji Bao. Fu Jian sent reinforcements led by Wei Zhong to attack Ji Bao, he defended for 2 years, and it can't be captured; finally it was captured because there was no backup.