Illinois State Geological SurveyThis line data layer represents interstates and toll roads for Illinois in 1996. The dataset was originally created by the Illinois State Geological Survey in 1996.[This data set contains interstates and toll roads for Illinois. This is a subset of the roads data set stored by county. Note that the functional classification of roadways is the jurisdiction of the Illinois Department of Transportation and is subject to change. Data are derived from the US Geological Survey 1:100,000 Digital Line Graph files, transportation layer, 1980-1986. Publication dates of the USGS maps used as sources range from 1980 to 1996. Major highways were updated as of 1996. The maximum estimated error in horizontal position based on National Map Accuracy Standards is 167 feet. Attributes include up to three interstate route numbers.]Shapefileark:/77981/gmgsgt5ff24engPublicInterstates and Toll Roads Illinois {1996}DatasetsIllinois1996American Geographical Society Library – UWM Libraries