When it comes to the large-scale battle of crossing the river, people will immediately think of the battle of crossing the river launched by the China People's Liberation Army on April 20th, 1949. It took only three days for a million mighty men to cross the natural barrier of the Yangtze River, conquer Nanjing, the stronghold of the Kuomintang, and completely destroy the Chiang family dynasty. The first large-scale battle across the natural barrier of the Yangtze River in China's history was the battle of the Western Jin Dynasty to wipe out Wu in 280 AD, which was called Jianggong in history.

As early as 18, before the campaign of national reunification was launched, the grand strategy of destroying Wu was put forward, that is, the Bashu was decided first, and three years later, the land and water went hand in hand, breaking the construction industry and completing reunification. The real implementation of this strategy has reached the hands of his son Sima Yan. It took ten years to prepare for the extinction of Wu Dongzhi's light in the Western Jin Dynasty. One of the most important preparations is to appoint Wang Zhuo as commander of the water army, build ships and train the water army on a large scale according to the suggestion of veteran yang hu. Only by building a water army capable of fighting can Wu Dong be completely leveled. This is a summary of historical experience. At that time, Cao Cao could not defeat Wu Dong because there was no strong water army. The warship built by Wang Meng is about 120 step. Each ship is several stories high and can accommodate more than 2000 soldiers. It can ride on horseback and is very stable. It was an aircraft carrier at that time.

At this time, Soochow also welcomed its last emperor Sun Hao, who was dissolute and stubborn. The planks of Wang Zhuo's warships drifted to the territory of Wu, and many ministers reminded us to strengthen the defense in the middle and upper reaches. However, Sun Hao's original thinking still stays in the last victory over Wei Jun, thinking that the Yangtze River is a natural barrier, and no one can break it. In 280 AD, Emperor Wu of Jin made all preparations for the destruction of Wu, and sent Du Yu and other six people to lead the Sixth Route Water Army, totaling 200,000, and went hand in hand to take Jianye, the capital of Soochow. The combination of land and water, multi-channel advance, can completely disintegrate Dongwu's defense front along the river like cutting melons and vegetables, so that it can not care about the head and tail. The main force of the army in the Western Jin Dynasty is the 80,000 water army led by Wang Zhuo, who will descend from Sichuan along the river.

Du Yu, Sima Yi, Wang Rong and other army generals' tasks are to dismantle all defensive fortresses along the Yangtze River, remove obstacles along the Yangtze River, and cooperate with the advancement of the water army. Wu Dong also has more than 200,000 troops, and the total strength of the Western Jin Dynasty is only 200,000, which is not dominant. Wu Dong needs to disperse its forces to defend the Yangtze River and the south of the Yangtze River, which gives the Western Jin Dynasty the advantage of concentrating superior forces and dividing them one by one. Du Yu, a generation of famous soldiers, played a mainstay role in the battle with Wang Zhuo Water Army to conquer Jiangling, an important town in the Yangtze River. Finally, the three armies of the Western Jin Dynasty, Sima Fu, Wang Hun and Wang Zhuo, arrived at the gates of Jianye. Sun Hao, the late Emperor of Soochow, tied his hands behind his back and surrendered to Wang Zhuo's army with a coffin. Soochow made a complete curtain call. The Western Jin Dynasty ended the troubled times of the Three Kingdoms and completed the unification of Chinese territory.