The Battle of Ruxu (濡须之战) took place in 213–214 when Cao Cao led an army to the Yangtze at Ruxu (濡须, in modern Anhui). Sun Quan had built fortifications there to block northern advances. Cao Cao attacked; Sun Quan’s forces, including Gan Ning, defended the line. Gan Ning led a famous night raid with a hundred horsemen that struck Cao Cao’s camp; he returned without losing a man. After months of fighting Cao Cao could not break through and withdrew. The battle showed that Wu could hold the river and that Cao Cao’s hope of a quick conquest of the south was unrealistic.
Battle of Ruxu 濡须之战
Cao Cao and Sun Quan fought at Ruxu on the Yangtze in 213–214. Sun Quan's forces, including Gan Ning, held the line; Cao Cao withdrew. The battle confirmed the Yangtze as the border.