Great Britain. Ordnance SurveyThis is a digital index map to serve as a finding aid for the Seventh Series of One Inch Maps Ordnance Survey of Great Britain 1:63,360GeoJSONark:/77981/gmgstdz0c0vengPublicOpenIndexMap: Seventh Series of One Inch Maps Ordnance Survey of Great Britain 1:63,360Maps1940 to 1965American Geographical Society Library – UWM Libraries