Autonomous Region of Xinjiang) and continuing on-wards to Kazakhstan. The railway of Yumen is the linking point of the railway line between Lanzhou (capital of Gansu) and Ürümqi. After the discovery of oil in the Jiuquan basin, to the north of the Qilian Mountains the city's economy was given another major push. The first oil was drilled at Laojunmiao near Yumen in 1939 where an appreciable production was achieved in 1941. Only until 1949 did large-scale development begin, and prospecting in 1950 revealed much larger reserves than had been speculated. Yumen has its own refinery but is also linked by pipeline to a refinery at Lanzhou. Other than oil drilling and refining, Yumen also has thermal and wind power-generating facilities. Manufacturing includes machinery, building materials, chemical fertilizers and process agricultural products. China appears to be constructing 120 missile silos near Yumen. Geography and climate Yumen has a cold desert climate (Köppen BWk), with an annual total precipitation of , the majority of which occurs in summer. Winters are long and cold, with a 24-hour average temperature of in January, while summers are very warm, with a July average of ; the annual mean is . The diurnal temperature variation reaches or exceeds for much of the year. With monthly percent possible sunshine ranging from 67% in March to 80% in October, the city receives 3,214 hours of bright sunshine annually. References Populated places along the Silk Road Cities in Gansu Jiuquan