In the Ming Dynasty, the largest inland river Cao shipyard in China was Qingjiang duzao shipyard. The Qingjiang shipyard of the Ming Dynasty is located along the canal between Shanyang (now Huai'an District) and Qinghe (now Huaiyin District) counties of Huai'an Prefecture. It is named "Qingjiang" because it is close to the Huai River. The largest inland shipyard in China in the Ming Dynasty was
During the Yongle period, the Qingjiang governor shipyard was responsible for manufacturing inland water tankers in southern areas such as Nanjing, Huguang, Jiangsu and Zhejiang.
According to the records of Cao Chuan Zhi in the Ming Dynasty, from the third year of Hongzhi to the 23rd year of Jiajing (1490-1544), the number of ships actually built by Qingjiang duzao shipyard is generally stable, with an average annual average of 519.
Qingjiang duzao shipyard has four major shipyards, Jingwei, Weihe, Zhongdu and Zhili, with a total of 80 branches. The plant extends along the canal for a total of 23 Li. （MingDaiQuanGuoZuiDaDeNeiHeZaoChuanAnShi）