Topographical, reconnaissance and operations (trench) maps and diagrams; Admiralty charts and naval operations diagrams (at 1:24 000 and 1:26 000); air photographs; sketches and panoramas of Turkey in Europe, Turkey in Asia, and the Dardanelles Straits. The series contains maps compiled and/or produced by the Directorate of Military Intelligence General Staff Geographical Section, the Ordnance Survey and the Mediterranean Expeditionary Force, and significant groups of captured Turkish maps. There are a number of graphic and textual indexes (WO 301/1-49). The series also includes maps used in the Gallipoli campaign itself, maps produced for the Dardanelles Commission in 1916, maps produced in connection with the establishment of the post-war neutral, international and demilitarised zones, with the Greco-Turkish confrontations, and with the compilation of Official Histories.
Any convenient scale was used for operations maps produced in the field; only the later operations maps, usually compiled from air-photographs by GHQ, MEF, were produced in regular series to consistent scales. Because of the circumstances in which they were produced, scales and their representative fractions (RF) were on occasion given incorrectly on maps.