The "Li Wanzhi Incident" occurred in November of the forty-ninth year of Xi (1710). What happened was: Li Wanzhi, a native of Weiyuan, Ping'an Road (now part of Cijiang Road) in North Korea, and nine other people "crossed the border at night to collect ginseng. At dusk, they killed five people from the Qing Dynasty and looted their ginseng goods." In order to prevent similar incidents from happening in the future, In February of the 51st year of Emperor Kangxi's reign (1712), Qing Dynasty official Ula Mukeden and his entourage were dispatched to Changbai Mountain to jointly survey the Sino-North Korean border with North Korean officials. In the fifty-first year of the reign of Emperor Kangxi of the Qing Dynasty (1712), it was a national boundary monument defined between the Qing government and the Korean state. The demarcation monument is located at an altitude of 2,200 meters. The inscription records that "Yalu is in the west and Tumen is in the east, so a stone was laid on the watershed to mark it." However, the boundary monument is located in an inaccessible area and has gradually been forgotten by people. China and North Korea re-investigated the boundary marker in 1883. Unexpectedly, the two sides put forward completely opposite claims about "Tumen".

On April 27 (May 31), Mukeden and his party arrived in Houzhou and met with North Korean reception officials. On May 4th (June 7th), Chinese and North Korean officials arrived at Huishan, and on May 11th (June 14th), a group of people climbed to the top of Changbai Mountain. Muke registered the water source as follows: "A few feet north of it, the water overflows into a waterfall, which is the source of the Heilongjiang River (today's Songhua River)... About three or four miles down, you can get to the source of the Yalu River. There is a spring bubble coming out of the cave. , less than a hundred steps, the gorge is in the middle of a large ravine,...and then turn eastward and cross a short hill, and there will be a spring flowing eastward, but after more than a hundred steps, it will diverge in the middle, and then it will come together." After finding the source of the Heilongjiang River flowing north (today's source of the Songhua River) and the source of the Yalu River flowing west, Mukeden consulted with Jin Qingmen, the translator of the Korean Li Dynasty, and concluded that "the Tumen source is hidden in the ground, and the boundaries are unclear, so we should not take it lightly." We discussed erecting a monument." So he went with officials from China and North Korea to search for the source of the Tumen River. "After examining for sixty miles, at dusk, they both said, 'Fruits flow eastward.'" After confirming that the place was indeed Tumen. After the water source of the river, Mukeden and officials from China and North Korea ordered people to cut stones and set up boundary monuments with inscriptions. The horizontal inscription on the monument read "Qing Dynasty" and the vertical inscription read: "Mukeden, the general manager of Wula, came here to inspect the border. To the west is Yalu." (Yalu River), and Tumen River (Tumen River) to the east, so a stone was laid on the watershed to record it on May 15, the 51st year of Kangxi's reign. There are words such as "Prime Minister, Envoy Xu Liang, Pu Daochang, Tongguan Jin Yingxian, Jin Qingmen". On May 28 (July 1), Mukeden and others went down the mountain to Musan to discuss with North Korean officials the issue of setting up a border fence on the upper reaches of the Tumen River. On June 2 (July 5), North Korea's envoy Park Quan and others responded and agreed to erect the fence. The specific situation of setting up the fence is: "Twenty-five miles below the self-erected stele, there is either a wooden fence or a pile of stones. The source of the water is five miles away, and the dry river is more than twenty miles away. The mountains are high and the valleys are deep, and the traces of the rivers are clear. In order to set up a mark, there are fences for more than 40 miles from the bottom to the outflow. There is no wood or stone in the middle, and the soil is strong, so only earth mounds are set up. "On the third day of the 11th month ( On November 30th), the King of Korea sent a "Boundary Demarcation Table" to the Emperor of the Qing Dynasty, saying: "Specially to clarify the border affairs, strictly prohibit the two places, and refer to the water as the limit, to indicate the north and south of a mountain, and set up stones to engrave it. To save the trouble of the poor country,... to eliminate the danger of the people from invading the country, and to use it as a permanent map."

The Sino-Korean boundary line in history has been clearly surveyed and demarcated, and the relevant records have been preserved. According to the legal documents, there is no issue of territorial disputes at all. That is to say, the China-North Korea boundary line is based on the traditional boundary line that was gradually formed during the exchanges between the two countries and is based on the boundary ridge of the Yalu River, the Tumen River and the source of the two rivers - the Changbai Mountain in the middle section of the China-North Korea border. The boundary line between China and North Korea jointly surveyed by Chinese and North Korean officials in 1712 (the 51st year of Kangxi's reign) has legal significance.

The site of the Changbai Mountain Boundary Ridge Monument on the China-North Korea border, the source of the Yalu River and the Tumen River, is at the eastern foot of Changbai Mountain, close to the North Korean side, not where the Tianchi Lake on the top of Baekdu Mountain is today. . Because according to Mukeden's boundary demarcation records, the final source of the Tumen River was about sixty miles away from the source of the Yalu River. "The west is Yalu and the east is Tumen, so a stone was cut on the watershed to mark it." The historical facts that can prove this theory are:

In 1885, when Chinese and Korean officials re-examined the source of the Tumen River, they found that there were three waters at the source of the Tumen River: Xidou water, Hongdan water, and red earth mountain water. Among the three waters, "Only the red red water is located in the east of Baishan Mountain, facing the source of the Yalu River. It is consistent with the meaning of examining the inscription on the east Yalu West Tumen". Representatives of the Qing court therefore advocated that the Hongdan River be the source of the Tumen River to determine the national boundary between China and North Korea. Li Chongxia, a representative of the Li Dynasty of North Korea, said that under the foothills of the Rouge Mountain in the south of Changbai Mountain, there is a Sino-Korean boundary stone, which was the boundary demarcation and inspection sign of Mukden of the Qing Dynasty in 1712.

After the two sides met, Deyu, a representative of the Qing court, and others believed that the Mukeden inspection stele was originally erected at the watershed of Xiaobai Mountain, as evidenced by the inscription "Tumen in the east, and Yalu in the west." Now it appears in Rouge Peak in Changbai Mountain. Rouge Peak is far away from the source of Yalu and Tumen rivers, and its name does not match its reality. It can be concluded that this monument was moved here privately. In 1887, when representatives from both sides re-explored the source of the Tumen River, they discovered Shiyi water at the source. Therefore, in the following year, the Qing court built ten stone steles "Hua, Xia, Jin, Tang, Gu; He, Shan, Dai, Li, Chang" to replace the original boundary signs (wooden signs) erected along the Tumen River. ) to last forever. The places where they were erected in sequence are: a monument with Chinese characters on the top of Xiaobai Mountain, a monument with summer characters at the mouth of the ditch at the east foot of Xiaobai Mountain, a gold-character monument at the head of Huanghuasongdianzi where it meets the ditch, a monument with soup characters at the end of Huanghuasongdianzi at the mouth of the ditch, and a stone monument with Chinese characters. A monument with the word "river" is erected at the source of Yi water, a monument with the word "river" is erected at the intersection of Shiyi and Hongtu water, a monument with the word "mountain" is erected on the south bank of the Changpo pontoon bridge, a monument with the word "mountain" is erected at the intersection of Shiyi water and Hongdan water, and a monument with the word "Sanjiangkou" is erected at the confluence of Jiangxi Doushui River. Monuments with a long character are erected at Tumen River and Pu River (starting from the "Hua" monument on the top of Xiaobai Mountain in the southeast of Changbai Mountain and ending with the "Chang" monument at the confluence of Pu River and Tumen River). Chinese scholars even used seven kinds of historical documents from China and North Korea to verify that the inspection stele erected by Mu Keden during his inspection of the border between China and North Korea in 1712 was located at the watershed of Sobai Mountain. They further discussed the circumstances and reasons for the subsequent move of the stele. , the conclusion is irrefutable. To sum up, it can be seen that according to the China-North Korea boundary line jointly surveyed by Chinese and North Korean officials in the 51st year of Emperor Kangxi of the Qing Dynasty (1712), Changbai Mountain belongs to China, not North Korea. This is proved by legal documents. The territorial dispute between China and North Korea began in 1962, when the Government of the People's Republic of China and the Government of the Democratic People's Republic of Korea signed the China-North Korea Boundary Treaty in Pyongyang. As the boundary, one-half was given to North Korea (North Korea later changed the name of Baekdu Peak to General Peak). The purpose of this move by the Chinese government at that time was out of the consideration of the friendship between China and North Korea - "comrades plus brothers", and to set the border back from the joint demarcation line between China and North Korea in 1712 (the 51st year of Kangxi). However, what the Chinese side did not expect was that the Chinese government gave up more than half of the Changbai Mountain Tianchi Lake to North Korea. Not only did the South Korean side not appreciate it, but it made further demands on China (part of which was the concession of the Changbai Mountain Tianchi Lake, which changed The relatively flat and undisputed old boundary line originally surveyed by China and North Korea).