China's Grand Canal

The Grand Canal is a series of waterways in eastern and northern China starting at Beijing and ending at the city of Hangzhou in Zhejiang province, linking the Yellow River with the Yangtze River. Stretching some 1,800 km, it is the world’s longest man-made waterway, and constitutes one of the world’s largest and most extensive civil engineering project prior to the Industrial Revolution. At its peak, it consisted of more than 2,000 km of artificial waterways, linking five of China’s main river basins. The canal was built to enable the transport of surplus grain from the agriculturally rich Yangtze and Huai river valleys to feed the capital cities and large standing armies in northern China. Since then, it has played an important role in ensuring commerce and cultural exchange between the northern and southern regions of eastern China and is still in use today as a major means of communication.

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The canal was built in sections in different areas in different periods, starting from 5th century BC, but it wasn’t until the 7th-century when a major expansion was carried out, under the direction of Emperor Yang of the Sui dynasty, bringing the canal to the magnitude it’s known for today. Emperor Yang needed a way to move rice from the fertile region around the Yangtze northwest to feed his capital and his armies which were constantly battling nomadic tribes. More than 3 million peasants were pressed into service, supervised by thousands of soldiers. The project took six years to complete, but by that time, approximately half of the peasant workers were dead of hard labour and hunger. But for all the sufferings, the canal proved indispensable for the movement of food supplies. By the year 735, nearly 150 million kilograms of grain were shipped annually along the canal. Other goods, from cotton to porcelain, were also traded, helping China’s economy bloom.

When the Mongol Yuan dynasty (1271–1368) moved the capital of China to Beijing, it eliminated the need for the canal arm to reach west to Kaifeng or Luoyang. A shortcut was made over Shandong province which shortened the length of the Grand Canal by as much as 700 km, and set the present route of the Canal.

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In the middle of the Ming dynasty (1368-1644) the canal was overhauled, and a series of fifteen locks was engineered in western Shandong. By this time the imperial transport army had grown to 15,000 boats and employed 160,000 soldiers who supplied the manpower to pull loaded barges when necessary. The successive improvements to the canal allowed the rulers to more easily conduct tours of inspection of their holdings to the south, enabling a greater control of their realm.

Construction of the canal led to many extraordinary engineering innovations. In 587, the world’s first lock gates were invented by the Sui Dynasty engineer Liang Rui for one of the canal’s original sections along the Yellow River; in 984, a transport commissioner named Qiao Weiyo invented the Grand Canal’s first pound lock – the lock that we see in modern canals even today.

When railway became available, the canal gradually fell into disuse and disrepair. Today, only the section from Hangzhou to Jining is navigable. The central and southern sections are maintained and used mainly to transport coal from the mines in the Shandong and Jiangsu provinces. Other sections of the Grand Canal have suffered from a build-up of mud and the northernmost section has all but dried up.