Also known as Little Square Plate City, Yumenguan Pass (Jade Gate Pass) served as a strategic fort along the ancient Silk Road. It was said that the jade from Hetian (presently Xinjiang Province) was transported to the central plains of China through Yumenguan Pass, hence its name of Jade Gate Pass. Along with Yuangguan Pass, Yumenguan Pass protected Dunhuang against invasion from the Western Regions in ancient times.
Rammed with earth, Yumenguan Pass is 26 meters (85 feet) long from north to south and 24 meters (79 feet) wide from east to west. Its wall is well-retained, being 3 meters (10 feet) wide at the top and 5 meters (16 feet) wide at the bottom, and has gate openings in the west and north respectively.
Driving along the 215 National Road from Yumenguan Pass and crossing the Aerhchin Mountains, you can reach Tsaidam Basin of Qinghai Province, Ruoqiang of Xinjiang Province and Lhasa of Tibet, along which you can appreciate the boundless stretch of the Gobi Desert, the fantastic mirages, the vivid sleeping Buddha and the sand plants in the desert. Yumenguan Pass is accessible by a two hour coach journey. The views of the vast golden dunes of the Singing Sand (Mingsha) Mountains to the south are the highlights of the arid landscape.
Yumenguan Pass was mentioned in many poems, of which Lyrics to Liangzhou Tune by Wang Zhihuan of the Tang Dynasty (618-907) stands out, and it reads:
The Yellow River riseth up far into clouds so white,
An isolated city on mountains standeth sky-high.
The flute is futile the weeping willows tune here to blow,
In that beyond the Jade-gate Pass spring breezes never go.
Yumenguan Pass has a history of 2,000 years. The warlike Huns were a great threat to the Western Han Empire, and they defeated Donghu in the east and Dayueshi in the west and occupied the Hexi Area (referring to the west of Gansu Province and Qinghai Province in the Han (206 BC-220) and the Tang (618-907) dynasties), based on which they attacked the Huns-Han border repeatedly in the early Western Han Dynasty (206 BC-9 AD).
In order to appease the Huns, the Western Han rulers adopted a peace-making marriage policy with them at the beginning, which was abolished by Emperor Wu of the Western Han Dynasty (206 BC-9 AD); instead, he ordered a crusade against the Huns. In the 2nd year (121 BC) of the Yuanshou Period, Emperor Wu ordered the General of the Flying Cavalry, Huo Qubing, to attack the Huns, ending up with defeating the right-wing of the Huns' army.
In the same year, Emperor Wu divided the Hexi Area into Wuwei Prefecture and Jiuquan Prefecture, and Zhangye Prefecture and Dunhuang Prefecture were added to the Hexi Area in the 6th year (111 BC) of the Yuanding Period of the Western Han Dynasty (206 BC-9 AD). At the same time, Yumenguan Pass was built under the orders of Emperor Wu.