This series contains 1:633,000 base maps overprinted with information required by other government departments. They were first produced in the mid-1920s. The earliest of these maps each consisted of three sheets: Northern (Scotland north of Berwick upon Tweed), Central (England, Wales and Scotland between Berwick and King's Lynn) and Southern (England and Wales south of King's Lynn). From the 1930s onward, there were two sheets: sheet 1 normally shows Scotland and England north of Richmond, Yorkshire, and sheet 2 shows the rest of England and Wales. The Isle of Man is included on these maps, although the Channel Islands are not. Descriptive booklets accompany several series of the maps.
The series includes maps produced for the Geological Survey of Great Britain; outline, physical and relief maps; demographic maps showing changing distribution of population between censuses; maps showing industrial locations and resources for the Board of Trade, maps of the road and rail networks for the Ministry of Transport; maps showing administrative boundaries, the nationalised Gas and Electricity Board areas and land classification and usage.
The material in this series is non record material originally held in the Library.