Grand Canal of China Built

In 605 AD, Emperor Yang of the Sui dynasty ordered a massive building campaign that linked northern and southern China by water. The result, later known as the Grand Canal, became one of the largest engineering projects of the premortern world. Stretching roughly 1,800 kilometers in its later form, it is generally regarded as the longest artificial waterway ever built, and parts of it still carry traffic today.

The canal grew out of political and economic necessity. China had been divided for nearly three centuries before the Sui reunified it in 589. The political centers lay in the north, around Chang'an and Luoyang, but the rice-rich lands of the Yangtze valley in the south produced the surplus needed to feed the court and armies. China's main rivers flow west to east, so moving grain north and south was slow and costly. A north-south artery would bind the reunified empire together and strengthen the dynasty's control.

The Grand Canal was not built entirely from scratch. Earlier rulers had dug local channels, some dating back many centuries before the Sui, and the project connected, widened, and extended these into a coherent system. Under Yang, work began in 605 with a canal linking Luoyang to the Huai River and the Yangtze region, and further sections were added over the following years, including a northern branch toward the area of modern Beijing. Sources say that millions of laborers, including conscripts, were mobilized, though the exact numbers and death tolls are uncertain and may be exaggerated in traditional accounts.

The human cost was heavy. Together with costly military campaigns, especially failed invasions of Goguryeo in Korea, the forced labor stirred widespread resentment. Rebellions spread, and in 618 Yang was assassinated and the Sui collapsed, after only about three decades in power. Traditional Chinese histories, written by successor dynasties, tend to portray him as a tyrant, though modern historians often credit him with farsighted ambitions.

The canal outlasted the dynasty that built it. Under the Tang, it became the backbone of the empire's grain transport, and later dynasties repaired, rerouted, and expanded it. The Yuan shortened the route to reach their capital at Dadu, and the Ming and Qing maintained it as a vital supply line. It encouraged the growth of cities such as Yangzhou and Hangzhou and fostered commerce and cultural exchange between regions.

Railways and sea transport eventually reduced its importance, and some stretches silted up or dried out. Yet sections remain in use for shipping, and in 2014 UNESCO inscribed the Grand Canal as a World Heritage Site, recognizing it as a lasting monument to human labor and imperial ambition.