According to one estimate, the British war effort alone saw 34 million topographic maps being produced between 1914 and 1918 for use on the Western Front. The process of producing these maps, and supplying them to the front, involved not just the Geographical Section of the General Staff (GSGS) but also the Ordnance Survey, both in England as well as in northern France. The trigonometrical networks that underpinned the larger-scale (1:20,000) ‘trench maps’, that British and allied forces used on the frontline, crucially depended on the field-surveyors’ work. To examine the geodetic accuracy of the maps that the British army made, and the effectiveness of the field-survey operations on the Western Front in 1917, twenty-first century spatial technologies are used here to analyse a group of trench maps for the area of Messines (Mesen), near Ypres (Iepr), in Belgium. Analysing the map-series for one particular part of the frontline offers some otherwise unrecorded insights into the field practices of the surveyors, mainly from the Royal Engineers’ Field Survey Companies (FSCs), and reveals some of the material impacts that the battlefield had on these men and their work, their ability to navigate and survey, accurately, the mutilated landscapes of the Western Front.

Keith Lilley is Professor of Historical Geography at Queen's University Belfast and has particular expertise in interpreting historic landscapes, maps, and built environments. Between 2014 and 2020 he directed the AHRC-funded WW1 Public Engagement Centre, "Living Legacies 1914-18" and undertook research and outreach using mapping and survey, including developing new online interactive digital mapping resources for the Centenary of WW1 coproduced with UK heritage organisations and community groups. Using GIS to analyse historic maps, he led new research on WW1 cartography and field-surveying, reflecting his interest in tracing global histories of survey practices and geodetics. In recognition of Prof Lilley's professional contribution to Geography, in 2018 he received from the Royal Geographical Society (RGS) the Cuthbert Peek Award, "For advancing geographical knowledge through the application of contemporary methods, including GIS and mapping."