UNESCO's description says that the Grand Canal was built in sections from the 5th century BCE; that only under the Sui did the idea arise of joining the sections into one route for the whole empire; and that under the Yuan it reached a new peak, linking five great river basins with more than 2,000 km of artificial waterways. The canal's starting point appears in the Zuo Commentary for the ninth year of Duke Ai (486 BCE): "In autumn, Wu walled Han and cut a channel linking the Yangtze and the Huai." The entry says only that Wu did this; because the entry for Duke Ai's first year already records that "King Fuchai of Wu defeated Yue at Fujiao", later writers credit King Fuchai of Wu with digging the Hangou.
The Sui joined the sections into a trunk route. The Book of Sui, Annals of Emperor Yang, records that in the third month of Daye 1 (605) Emperor Yang of Sui "called up over a million men and women from the commanderies south of the Yellow River and cut the Tongji Canal", drawing the Gu and Luo waters to the Yellow River and drawing the Yellow River from Banzhu to the Huai; in Daye 4 (608) he again "called up over a million men and women from the commanderies north of the Yellow River to cut the Yongji Canal, drawing the Qin River south to the Yellow River and north to Zhuojun". The Yuan added new sections: in Zhiyuan 26 (1289) it opened the Huitong Canal "to carry the goods of north and south"; in Zhiyuan 30 (1293) the Tonghui Canal, directed by Guo Shoujing of the Directorate of Waterways, was completed. Before it, official grain had been carried overland for the fifty li from Tongzhou to Dadu; afterwards "the capital was spared the labour of overland haulage" (History of Yuan, Treatise on Rivers and Canals). So the Beijing-Hangzhou Grand Canal, from Dadu in the north to Hangzhou in the south, came into being.
The weight of the canal lies in how it held together a state whose capital was in the north and whose grain and taxes came from the south. Chen Chao, a research fellow at the Anhui Provincial Institute of Cultural Relics and Archaeology, points out that after China's economic centre moved south in the Wei, Jin and Northern and Southern dynasties, the north remained the political centre; in his view the Sui and Tang dug and maintained the canal to hold this pattern together, and grain transport carried taxes, grain, coin and silk from every region to the capital along it. UNESCO's description also says that the canal was long managed through the Caoyun system, the court's monopoly on the transport of grain and important raw materials, linking the farming economy to the food supply of the court, the people and the army. The Ming choice bears this out. The History of Ming, Treatise on Rivers and Canals, records that when the Yongle emperor built Beijing, grain was at first "shipped from the south-east, hauled by water and by land", with sea transport also used; in Yongle 9 (1411) he ordered the minister Song Li and others to dredge the Huitong Canal; the same chapter records that the works of Chen Xuan at Qingjiangpu were completed in the fifth month of Yongle 13 (1415), and goes on: "From then on grain shipments went straight to Tongzhou, and both sea and land transport were abandoned." In the Qing, canal transport wound down from the middle of the nineteenth century: the Draft History of Qing, Treatise on Food and Money, says that "canal transport stopped from Xianfeng 3"; in 1855 (Xianfeng 5) the Yellow River broke its banks at Tongwaxiang, and "the canal route was blocked still more"; and in 1901 (Guangxu 27) the court, "because funds were exhausted", ordered that from that year the provinces' canal and sea shipments "all be levied in money instead".
The canal also changed life and culture along its banks. Chen Chao holds that the opening of the canal promoted trade along it, that "the cities on both banks thrived in every trade, with a strong air of commerce", and that culture spread along with the goods. Judgements on the digging of the canal, by contrast, have differed. Pi Rixiu of the Tang, in Recalling the Past on the Bian River, wrote of the Bian, the line of the Sui Tongji Canal: "All say the Sui fell because of this river, yet to this day a thousand li depend on its flowing waves. Had there been no water palaces and dragon boats, its merit would be little less than Yu's." The poem says that people blamed the fall of the Sui on the river, and also points out that a thousand li of waterway still depended on it; in his view, had there been no royal pleasure voyages on dragon boats, the merit of digging it could be weighed against Yu's taming of the floods. In 2014 the Grand Canal was inscribed on the World Heritage List, and UNESCO's description says it is still in use today.
The canal is bound up with three other canons. With Yellow River Harnessing: the Draft History of Qing records the river's hold on the canal route: when the Yellow River broke its banks at Tongwaxiang in 1855 and flowed by Zhangqiu into the Daqing River, "the canal route was blocked still more". With the Shoushi Calendar: Guo Shoujing, who directed the Tonghui Canal, was also one of the officials who presented the new calendar. The History of Yuan, Biography of Guo Shoujing, records that when the new calendar was completed in Zhiyuan 17, Guo memorialized together with the other officials; it also records that in Zhiyuan 30 Khubilai, returning from Shangdu and passing the Jishuitan, "saw the boats covering the water", was delighted, and named the canal Tonghui. In the Yuan, Guo Shoujing took part in both the making of the calendar and the opening of the canal. With Marketplace Hubs: Chen Chao says that the cities along the canal had a strong air of commerce; the boats and goods coming from north and south brought trade to the markets of the cities on its banks.
A state with its capital in the north and its grain and taxes in the south depended on this canal to carry the southern levy to the northern capital, and this is the root of its standing as a canon. The histories record that when the grain route changed, the institutions changed with it: from 1415 Ming grain shipments went straight to Tongzhou and sea and land transport were abandoned, while in the Qing canal transport stopped in the Xianfeng years and in 1901 the grain levy was commuted to money. It is bound up with other canons too: the Yellow River's breach left the route "blocked still more", Guo Shoujing both took part in the calendar and directed the Tonghui Canal, and the cities on its banks thrived in every trade. Pi Rixiu, writing of the Bian River, even said that but for the dragon boats, the digging could be weighed against the work of Yu.
The Grand Canal is the class in the chapter on Infrastructure on the waterway between north and south. It covers the artificial waterway running north to south across five river systems: it began with the Hangou of Wu in the Spring and Autumn period, was joined into a whole under the Sui and straightened under the Yuan, and became the grain-transport route from Dadu in the north to Hangzhou in the south, linking the political centre with the economic heart.
