Definition of "Yumen"

Rich oil has been found in the vicinity of Yumen County north of the Chilien, and a new oil city has been built there.

1958, Chun-heng Wang, “The Shensi-Kansu-Chinghai Region”, in A Simple Geography of China (China Knowledge Series)‎, Peking: Foreign Languages Press, page 202

After landing at Chiuchuan, we set out immediately up a macadamised highway to the oil municipality of Yumen situated up on the slopes of the Chilien Mountains in what was once known as Yumen County.

1973, Rewi Alley, “Through the Kansu Panhandle and Down the Old Silk Road”, in Eastern Horizon‎, volume XII, number 6, Hong Kong: Eastern Horizon Press, page 20, column 2

Yumen is in a high-altitude corner of the poor northwestern province of Gansu. A single oil field is its gushing but fragile economic base.

2008 April 17, “Many of China's 'resource' towns are dying”, in The New York Times‎, archived from the original on 24 May 2021, International Business‎