There have always been different views on the site of Yumenguan in Han Dynasty. Some ancient books in the Tang and Song Dynasties, such as Kuozhi and Yuanhe County Records, are considered to be located at 1 18 in the northwest of Tangshouchang County (now the site of Shou Chang, Nanhu Township, Dunhuang City). Dunhuang suicide note "Shazhou Map", "Shazhou City Ground Mirror" and "Shou Chang County Land" are believed to be located at the north 160 of Tangshouchang County. Since the beginning of this century, according to the Han bamboo slips such as Yumen Dewey written by Xiaofangcheng, about 80 kilometers northwest of Dunhuang, many scholars believe that this city is the Yumen Pass of the Han Dynasty. It is also believed that the earliest Yumen Pass was located in the east of Dunhuang, or near Hanyumen County (now Jinchi Town, Yumen City). In the second year of Tai Chu (BC 103), Li Guangli cut Dawan and moved to the northwest of Dunhuang. In recent years, Gansu Provincial Museum and Dunhuang Museum have proved that Yumenguan should be located in the east of Linyao Lane and the west of Yumen Houguan Lane (Ma Quan Bay), which seems to be 0.6km southwest of Ma Quan Bay Site and 1 1 km west of Pan Xiaofang, according to the Han bamboo slips unearthed from the beacon tower site in Dunhuang and Ma Quan Bay, as well as the local topography and the relevant location of the post road. But the site of Guancheng has never been found, or it has been destroyed. Although the above viewpoints are different, they all think that Yumenguan in Han Dynasty was located in the northwest of Dunhuang, and it has not changed since the end of Han Dynasty. A large number of bamboo slips unearthed from beacon towers along the Great Wall in Dunhuang also prove this point.
In addition, the Sihe River in the northwest of Sishui Town, Xingyang City enters the Yellow River estuary. Named after Yumen, the north gate of the ancient city of Gaocheng. It is located between Daishan Mountain and Guangwu Mountain, and the ancient Sishui flows into the Yellow River from the north of Guankou. In the first 203 years, in order to avoid Xiang Yu, Liu Bang went from Gaocheng to Yumenguan and crossed the Yellow River to Xiuwu. "Notes on the Water Classics Five Rivers": "South of Yumen." That's it. It is the throat of traffic in the north and south of the Yangtze River. Therefore, the "Sishui County Records" records: "Tiger Prison is the hub of things, Yumen is the throat of the north and south."