Regarding the existence of the grand canal of the foster system,

 1,515km long. It was originally 1,782km long, but it was shortened in the process of large-scale restoration and expansion in 1958 by opening and opening between five large rivers, including the Haihe River, Hwanghe River, Huaihe River, Yangtze River, and Chentang River. This construction was carried out as part of the river network plan, such as flood prevention, farmland irrigation, and securing industrial water, as well as expanding the depth and width of the canal and straightening the curved area. Thirteen ports were built along the coast of the canal, and floodgates were installed to control a large amount of water flow. Outside Beijing's Zhu Anmen Gate, a dock was built that could dock 4,000-ton steamers, allowing 2,000-4,000-ton ships to operate from Beijing to Hangzhou. In China, there are many rivers flowing in the east-west direction, so water transport connecting east-west has developed since ancient times, while in the north-south direction, the Weihu River, a tributary of the Haihe River, and the Wohe River and Yinghe River have only been used locally as waterways in the southwest-northwest-southeast direction. Therefore, Daeunha has played an important role in connecting Hwabuk, which has long been a political center, and Gangnam, which was rich in supplies, as well as politically combining Hwabuk, Hwajung, and Hwanam. The history of the Great Canal has its origin in the early Jin and Han periods, and it is believed that the waterway from the Hwanghe River to the Huaihe River southeast and the Huaihe River and the Yangtze River were already open at that time, but were buried during the confrontation between the two Koreas. In addition, after the earthquake in the early 4th century, as the development of Gangnam progressed, the canal opened in the delta, but it was only mainly used locally. However, when the Su Dynasty unified the world and established itself in Jangan, Sanyangdok, Tonggeoeseo, Yeonggeoeseo, and Gangnamha were renovated one after another to complete the waterway connecting the south and north through Gangan. Sanyangdok and Gangnamha are the renovation of conventional canals, and the controller, that is, the change, is partially, and the removal of the spirit is a new renovation. The Su Dynasty soon collapsed, but during the Tang and Song periods, the Great Canal formed the aorta of inter-Korean waterway transportation, contributing greatly to the water transportation and commercial development of Gangnam development. The Song Dynasty became a capital city in Kaifeng on the coast of the change because it was greatly influenced by such circumstances. When the Yuan Dynasty ruled China again and established itself in Daedo Island, the importance of the Great Canal increased, and the Jeju River, which leads from the Tsusui River in Shandong Province to the Daching River, and Hoetong River from there to the Weihu River were established. Thus, a waterway was formed from the Yangtze River basin to Tianjin by canal, and to reach near the national capital by using the Baihe River again. Except for the period when the capital was established in Nanjing in the early Ming Dynasty, the role of Daeunha was very large in Myeong and Cheongdae, and in particular, Myeongdae also focused on maintaining the canal, such as opening a direct water channel through Xuzhou. However, when shipping became prosperous at the end of the Qing Dynasty, the importance of the canal decreased relatively, and after the Republic of China took Nanjing as a national highway again, the trend worsened and was buried here and there. Then, after the establishment of the People's Republic of China, expansion and restoration work were carried out along with river planning. ------------------ Summary: 1. The history of the canal began from the dark ages.           2. The Daeunha of the foster ritual was renovated as if Qin Shi Huang had built the Great Wall of China, or a new part was created.           3. After that, it was renovated or lost. (Therefore, the location of the great canal of the foster system and the current canal is different.)--------------- In coo2, we doubt how the foster system made the Grand canal. (1) The Grand canal built by the Su Dynasty, that is, the Yeongmugeo, and the controller are over 1,100 kilometers from Beijing to Shanghai. (2) Su Nara was a country that did not exist for just 40 years without modernized equipment in the 5th and 6th centuries. This is because this article talks about the existence of the Great Canal as one of the grounds for affirmation or denial of the continental Baekje theory. Therefore, because of the existence of continental Baekje, the Great Canal did not exist in Habuk and Shandong provinces only a circular error.... That is, <Problem 1: Difference from Control Records> It is said that it starts in the southwest of Hanamseong Fortress and leads to recovery through the Yellow River, but it is incorrectly listed in Baekje textbooks. In addition, considering that there is no canal to the southwest of Nakyang, the record of Suseo should be reviewed. <Question 2: Difference from Yeonggeojeo Records> Yeonggeojeo is related to water flowing from Sanseo-seong to Hanam-seong to Habuk-seong, but there is Taehaengsanmaek Mountain Range, and in Gudangseo, Dangseo, Samguksagi, the ancient personality, sacred, stone gate, east of Dongmyeong, so the textbook seems to be incorrectly written. There are questions about whether there was a need for a canal from Sanseoseong to Hanam, and the connection of the place name of the canal. Rather, it is necessary to review the construction of a canal to advance from Sanseoseong Fortress to Eunsan and Sinseong Fortress in the northern part of Habukseong needs to be reviewed. ---------> This explanation means that it cannot be a basis at all... (1)There will be a map above that supports the explanation of... But this is a canal built in later generations...that is, it's not a canal built by the foster system... Also, you'll know when you go to coo2 If you look closely at the maps that use the grand canal of the foster system as the basis for denying it, all of them contain alphabets... In other words, it's a map that was made later on... But it doesn't make sense to claim that the Great Canyon of foster medicine actually existed on this map... Therefore, naturally, the argument of (3) is also denied... (2)According to his argument, Qin Shi Huang couldn't dare to renovate the Great Wall of China or repair the missing part. ----------- On top of other things, there is a question of "whether there was a need for a canal from Sanseoseong to Hanam," but this means that they are not aware of the historical fact of "Gangnam Development."