Eventually I discovered this was one of the largest iron and steelworks in China -- Shoudu Gang Tie Chang or Capital Iron and Steel Works ("Shougang" for short). Unfortunately, my schedule in Beijing did not allow time to explore its vicinity. However, in the early 2000s, on a warm day of clear blue skies, I went up to the viewing deck on China Central Television Tower. My plan was to capture a set of panoramic photo images of the city - amazing looking today at how much has changed since then! To the west, my attention was caught by an industrial landscape, close to the steeply rising Western Hills. An extensive line of smokestacks and cooling towers stretching for several kilometers where the urban spread of Beijing abruptly ends due to mountainous terrain beyond. Indeed that industrial site, at the peak of its development, ultimately covered an area over 700 hectares.

The steelworks had evolved out from an earlier pig iron plant dating from 1919 though massively expanded post-1949. It was located there in the western suburb of Shijingshan, partly due to the presence of vital raw materials for steel production accessible in the vicinity - water from the Yongding River, limestone deposits conveniently quarried. Nearby the valleys of Mentougou had an abundance of coal reserves. Once one of China’s earliest coal production basins, over a 20-year period its remaining 270 mines were closed down between 1999 and 2019 when the last of the pits ceased operation. Depending on wind direction and air movement, the mines represented serious polluting factors for the city and indeed the river.