Base map of Warren County. Plate one of a four plate map. Prepared by the New Jersey State Highway Department, Division of Planning in cooperation with the U. S. Department of Commerce, Bureau of Public Roads. State highways as of Dec. 31, 1967. Culture, county roads and municipal streets are as of 1940. Map series includes 17 insets. This plate includes an index of populations of towns and townships based on the 1940 census.