《旧唐书·列传·卷一百二十二》
计算水路进程，他必须越过高邮县界，这一带河岸陡峭而河窄水深。
计其水路，须出高邮县界，河岸斗峻而水深狭。
Calculating the progress of his water route, he must pass the border of Gaoyou County, where the river banks are steep and the river is narrow and deep.