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The Ling Canal is located in Xing'an County, Guangxi Province, and is also called the Xing'an Canal or the Xiang-Gui Canal. Because it was dug in the Qin Dynasty, it is also called Qin Chu Canal. So far, it has a history of more than 2,100 years. It is the oldest canal in the world together with the Hangou built by the Wu Kingdom in the Spring and Autumn Period.

Why did Qin Shi Huang dig this artificial canal? It turned out that after Qin unified the six kingdoms, in order to further consolidate the unified situation, while attacking the Xiongnu in the north, it also conquered Lingnan in the south. At that time, the Yue people living here were in the stage of slavery, and the slave owners dominated each side, forming a state of separatism and melee. Due to mutual attacks and robberies, the economy declined and people's lives were very miserable. Therefore, it has become an inevitable trend of historical development to open the north-south passage, end the chaos in the Lingnan region, and complete the reunification of China. From 221 BC to 214 BC, that is, from the 26th to the 33rd year of Qin Shi Huang, the Qin Dynasty continuously sent troops across the Five Ridges. In 219 BC, Qin Shihuang went on a tour to the upper reaches of the Xiangjiang River. Based on the need at that time to solve the problem of food and salary for the southern expedition troops, he made the decision to "envoy Jian Lu to dig canals to transport food." Under the leadership of the outstanding conservator Shi Lu, the Qin Dynasty sergeants and The local people worked hard together, splitting mountains and cliffs, building embankments and canals, and channeling the Xiang Water into the Li River. Finally, a more than 30-kilometer-long canal was built, opening up the main thoroughfare for north-south water transportation.

Between my country's Changliu River Basin and the Pearl River Basin. Across the towering Wuling Mountains, travel by land is already difficult, and water transportation is even more impassable. However, the upper source of the Xiangjiang River, a tributary of the Yangtze River, and the upper source of the Lijiang River, a tributary of the Pearl River, happen to be in Xing'an County, Guangxi, and they are only three miles apart. The low mountain ridge in the middle is only thirty meters high and one mile wide. The designers of Ling Canal took advantage of this geographical condition to create a waterway that led from Hunan to Li, meandering through the rolling hills, and connected the Yangtze River water system and the Pearl River water system.

The channel project of Lingqu Canal is very arduous and complex. All the way along the Nan Canal, it flows close to the mountains, and several cliffs blocking the road have to be broken along the way. Especially when crossing the watershed, that is, Taishi Temple, a river must be split from a stone mountain dozens of meters high. Such a project, without advanced machinery or explosives, relied entirely on hands and simple tools. It was impossible to complete it without overcoming great difficulties at the time.

In addition, the Lingqu canal runs through hilly areas with a steep slope and rapid water flow, making it difficult to sail a boat. In order to solve this problem at that time, the river was intentionally curved and circuitous in order to extend the flow and reduce the specific drop, which provided favorable conditions for the smooth and stable movement of the boat. At the same time, in order to further solve this problem, a steep gate, also called a bucket gate, is set up every other distance, which is a simple ship lock. In this way, the canal flow can be blocked in sections, and the ship can be raised or lowered section by section. This design method , more than two thousand years earlier than the Panama Cascade Canal built by the United States.

After the Lingqu Canal was completed, it played an important role in history. In the same year when Qu was established, Qin Shihuang conquered the Lingnan region and established the three counties of Guilin, Xiangjun and Nanhai, completing the cause of the Lingnan region. After the fall of Qin, the Central Plains region was in chaos. Zhao Tuo and Lu Jia successively launched rebellions and separatist regimes in Lingnan. Emperor Wu of the Han Dynasty also used this transportation line to contribute to the unification of the north and the south during the process of suppressing the rebellion. A large number of iron production tools have appeared in the Han tombs excavated in Guangdong and Guangxi, reflecting the development of the Guangdong and Guangxi regions. For two thousand years, Ling Canal has been an important channel for the north-south waterway and played a great role. Until the Ming and Qing Dynasties, the Ling Canal was still very busy.