DRG

Source: http://www.lib.ncsu.edu/gis/drg.html


DRG is an acronym for Digital Raster Graphics. These maps are scanned topographic maps & topographic maps only! They are also georeferenced. DRG must be be scanned at a minimum of 250 dots per inch. These dots are in this format because they are projected to the UTM, or Universal Transverse Mercator.

The map I have included in this post is of North Carolina State University. It is on a small grid displaying the campus of the school.