USGS Digital Raster Graphic (DRG) Files [Illinois]
A Digital Raster Graphic (DRG) is a scanned image of a U.S. Geological Survey (USGS) standard series topographic map, including all map collar information. The image inside the map neatline is georeferenced to the surface of the earth. DRGs are offered in the original USGS designated coordinate system of Universal Transverse Mercator (UTM) Zones 15 and 16 (with map collar) and also the entire state in UTM Zone 16 (without map collar; they provide a well-known, large-scale, digital base mapping layer. Learn more about��USGS DRGs(link is external).