These maps (tiled together below to create a larger image) were produced by the British Ordnance Survey in the years just prior to the outbreak of the First World War (1912-1914). The British knew the war was coming and were updating their topographic map coverage of the area, using the relatively new concept of contour lines to indicate elevations. However, they were planning for a traditional war of movement, not the stalemate of trench warfare it turned out to be. As a result, these maps were not made at a detailed enough scale to be useful other than for planning the logistics of things like supply and communication over very large areas.