Why the ancient Grand Canal was a "grain canal"?

After the Sui Dynasty unified the country, although the center of politics was still in the north, the center of economy had gradually moved south. At that time, the food supply of Chang'an, the capital city of the Sui Dynasty, depended to a large extent on the transportation of grain from the south.

However, the complicated transportation terrain outside Chang'an was quite unfavorable to the transportation, and the amount of grain reaching Chang'an by water was very limited. As a result, whenever Guanzhong was hit by a famine, there would be scenes of officials and citizens coming together to feed themselves in Luoyang.

Thinking about the scene of the city going to Luoyang, it was as magnificent as the modern spring transportation, which must have left a deep impression on Yang Guang, the later Emperor of Yang. Therefore, as soon as he ascended the throne, he moved the capital to Luoyang, which is surrounded by mountains on three sides and backed by the Yellow River.

While building Luoyang, Emperor Yang issued an edict to gather millions of workers to excavate the Tongji Canal and the Yongji Canal to the north and south, connecting Hangzhou and Beijing, with a total length of more than 2,700 kilometers, centering on Luoyang.

The opening of this "zigzag" shaped artificial river channel allowed grain from the south to be easily transported to the capital as well as to the north, thus opening up a prosperous period for China's water transportation.

2. Beijing-Hangzhou Grand Canal ("one" canal)

The Yellow River was often misbehaved in history, and several times it broke and changed its course, which had a major impact on the transportation of the Grand Canal every time. It carries an amazing amount of sand, and once it breaks into the Grand Canal, the sediment will silt up on the riverbed. This way the draft depth of the sailing ships has to become smaller or they will have to touch the bottom of the river.

During the Yuan Dynasty, Yuan Shizuizu Kublai couldn't sit still, he had to transport grain safely to the north to maintain the stability of his rule. So he began to reorganize the canal, to complete the Sui and Tang Dynasty Grand Canal "to take the straight and curved" of the vast project.

In the fall of 1292, Guo Shoujing, a water conservancy expert, dug the Tonghui River, which connects Tongzhou and the Jishuitan dock in Beijing, so that grain from the south could be transported directly to the city of Beijing. Beijing also established dozens of large and small granaries, effectively guaranteeing the food supply of the capital.

From then on, the Grand Canal no longer passes through Luoyang, but directly from Beijing to Hangzhou, showing a "one" shape, and we call it the "Beijing-Hangzhou Grand Canal". In this way, the Beijing-Hangzhou Grand Canal continued its prosperity in transportation.

Until 1885, when the Yellow River broke again, the canal system was once again greatly affected. At that time, the feudal dynasty was about to be launched into history, and could no longer afford to regulate the river, coupled with the rise of shipping and the opening of the Beijing-Shanghai Railway, the era was doomed to the decline of the canal.

3, the Grand Canal on the granary, grain ship

Grand Canal since it is the "grain canal", there is no doubt that the transportation of grain is its main burden of function, then where is the evidence? I'm in a hurry, I'm carrying it.

In 606 A.D., the second year after Emperor Yang ordered the canal to be dug, the famous granary "Huiluo warehouse" was built. According to current archaeological discoveries, Huiluocang was too big to be a small city.

This warehouse city east-west length of 1140 meters, 355 meters wide north-south, an area of more than 400,000 square meters. Archaeology *** found about 220 grain cellar, according to the distribution of the law of judgment at the time of the warehouse cellar about 700.

A grain cellar storage capacity reached 550,000 kilograms, if the 700 projected, then the total grain storage capacity reached 200 million kilograms, or 400 million pounds. And during the Sui and Tang dynasties, the total population of China was only 40 to 50 million, so it is evident that the grain storage capacity of Hui Luo Cang was huge.

However, Hui Luo Cang is not the most powerful, it is only the second. The biggest one is Xingluo Cang (also called Luokou Cang), which was built by the order of Emperor Yang of Sui Dynasty, the "first granary in the world".

Xingluo Cang (Luokou Cang) is a super granary, according to the "Old Tang Book" records "Cangcheng around more than 20 miles, wearing three thousand cellars, each cellar 8,000 stone, set the supervisor and the town of thousands of soldiers to guard."

These granaries were extremely significant in stabilizing the Sui Dynasty. When we look at the peasant revolts at the end of the Sui Dynasty, the Wagang army seized the Liyang Cang, Xingluo Cang (Luokou Cang), and Huiluo Cang along the Grand Canal, and all of a sudden left the city of Luoyang with no food to eat. In less than a year, the Sui Dynasty fell.

The next new dynasty that was established, the Tang, learned the hard way. After grieving through the Tongji Canal, grain ships from the south no longer delivered grain to the granaries around the city of Luoyang; instead, they passed through a section of the canal branching out from the Luo River and sent the grain directly to a barn city in the northeast corner of the imperial city of Luoyang.

This barn city, built in the eastern capital of Luoyang, was called "Hanjia barn," and when the site was discovered in 1969, it became a national sensation. In the archaeology, we found 287 grain cellars, one of which actually still had grain, and after more than 1,300 years, it was still well preserved: 48% carbonized, and 52% still contained organic matter.

The Tang Dynasty had a strict management system for food security issues, and some clues can be seen in the ruins of the Hanjia Cang, with grain cellar No. 160 as an example. This grain cellar is 11 meters in diameter and 6 meters deep; the bottom of the cellar is compacted and hardened by fire, then a mixture of burnt earth particles and carbon particles (a moisture-proof layer) is laid, followed by a mixed layer of wooden planks and hay, before the grain starts to be put in.

In addition to the star-studded national granaries along the Grand Canal, large and small grain ships traveled on the river, with tens of thousands of ships traveling daily during the heyday of the Ming Dynasty.

These ships were the cornerstone of imperial rule, and were managed by a single institution established by the emperor, the "Cao Yun Governor's Office". The Governor's Office was set up in Huai'an, Jiangsu Province, which was the hub for incoming and outgoing shipments.

The main grain-producing area of ancient China was in the south, and the so-called "Suzhou and Lake are ripe, and the world is full of them". Through the management of the Cao Transportation Governor's Office, the state was able to mobilize the grain from the south to the north in an orderly and safe manner, so that the north was free from the fear of grain.