1:100,000-scale Digital Line Graphs (DLG) from the U.S. Geological Survey
Digital line graph (DLG) data are digital representations of cartographic information. DLG's of map features are converted to digital form from maps and related sources. Intermediate-scale DLG data are derived from USGS 1:100,000-scale 30- by 60-minute  quadrangle maps. If these maps are not available, Bureau of Land …