The Jade Gate Pass is also called the Small Square Tray City, known in Chinese as Xiaofangpancheng. Towering on a sandstone ridge some 100 kilometers to the northwest of Dunhuang .built of rammed yellow earth, is well kept with two gates opened at west and north, Standing 10 meters high with 3meters in width at the top and 5 meters at bottom the city walls have parapets and bridle path leading to the top of the wall.
In the western Han Dynasty, the Yumen Pass used to be a prefect office and during the hundred years or so after the reign of Jianwu (25-56) of the Eastern Han, the pass underwent three times of rises and falls. And later in the Jin and Southern and Northern Dynasties wars were quite frequent in the area and also due to lthe open to traffic of marine route from east to west to Silk Road went declining. Towards the Sui and Tang dynasties, there appeared a thoroughfare, a shortcut between Jinchang (Anxi County ) and Yiwu (Hami City ). The pass was removed to Shuangtabao, somewhere near nowdays Anxi County and from then on, the Yumen Pass fell gradually intoobivion. With the pass blocked up ,walls gone dilapidated and no human traces to be seen along the pass became ruined ever since. The once prosperous atmosphere disappeared forever, falling into a desolate spot beyond which the breath of spring had never crossed.