DRG's, Digital Raster Graphics, are scanned images of USGS topographic maps (standard series) which includes all map collar information. They are georeferenced to the surface of the Earth and are designed to fit to the Universal Transvers Mercator projection. The map above is a portion of a DRG of Bushkill, Pennsylvania and it includes contour lines that represent elevation change. It also shows the border of two counties and a river. These maps can be used to determine the accuracy of a vector file.
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