Digital line graphs, or DLG, are maps released by the USGS in a variety of scales and are based upon other USGS maps of the same area that has already been produced. Just as DRG maps are simple and informative, the DLG map is similar to this format with the exception that it focuses more on actual land systems for it's basis. For example, there are many PLSS inspired maps available in areas of the United States it was implemented. This focus is invaluable to GIS users or any utilization of a USGS map. The map seen here is from the Illinois USGS and clearly shows relief features, roadways, and major landmarks to the local area such as the gravel pit and sewer disposal area. It does not, however, display any cartographic information intentionally unlike the DRG.
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