5921661 Royal Engineers repairing a bridge on the Western Front, 1918 (b/w photo) by Unknown photographer, (20th century); National Army Museum, London; (add.info.: Royal Engineers repairing a bridge on the Western Front, 1918. Photograph, World War One, Western Front (1914-1918), 1918. During the ?Hundred days? (8 August to 11 November 1918), the Allies launched a series of offensives along the line which drove the Germans back. The units of the Royal Engineers played a vital role in assisting the armies advance. Their work included road and rail repairs and bridging rivers and canals. From an album of 76 official photographs.); by National Army Museum ; out of copyright.