Si River

The Si River (Chinese: ; pinyin: Sì Shuǐ) is a watercourse located in Shandong Province and, in ancient time, in Jiangsu Province, China. It rises in the southern foothills of the Mengshan Mountains (蒙山) then flows through Sishui County, and the cities of Qufu and Yanzhou before emptying into Lake Nanyang (南阳湖). In ancient times the river was a large tributary of the Huai River, converging with the waters of the Fan (反), Sui (睢), Tong (潼) and Yi (沂) and numerous other rivers then passing through present day Yutai County, Pei County, Xuzhou City, Suqian City and Siyang County in Shandong and Jiangsu Provinces. At Sikou (泗口) (also known as Qingkou (清口), present day Huai'an City, Jiangsu), the Si River discharged into the Huai River. From very early on the Si River was connected with the Huai and Yangtze Rivers as well as the Central Plain of China for a long period in its history. In 1194, at the time of the Song and Jin Dynasties, the Yellow River altered its course southwards, engulfing the lower reaches of the Si River below Xuzhou City and those of the Huai River below Huai’an City. As a result, the Si River no longer exists in Jiangsu Province. In 1855, the Yellow River once more altered its course northwards. However, due to the large amount of silt carried by the river, it left behind a 4-to-6-metre (13 to 20 ft) high layer of mud in the lower reaches of the Si River’s former course.

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