5921670 Light railway and troops moving up, 1916 circa (b/w photo) by Unknown photographer, (20th century); National Army Museum, London; (add.info.: Light railway and troops moving up, 1916 circa. Photograph, World War One, Western Front (1914-1918), 1916 circa. Narrow gauge trench railways were used at the front for the supply of ammunition and stores, the transport of troops and the evacuation of the wounded. Trench railways linked the front with the standard gauge railway system further behind the lines. From an album of 76 official photographs.); by National Army Museum ; out of copyright.