Long Term Archive
1:24,000 Scale DRG
1:250,000 Scale DRG
A Digital Raster Graphic (DRG) is a scanned image of a USGS standard series topographic map, including all map collar information. The image inside the map neatline is georeferenced to the surface of the earth and fit to the Universal Transverse Mercator (UTM) projection. The horizontal positional accuracy and datum of the DRG matches the accuracy and datum of the source map. The map is scanned at a minimum resolution of 250 dots per inch.
DRGs have been made for all quadrangles in the USGS standard topographic map series for the United States, its territories and trusts. Source maps include:
DRGs are in TIFF 6.0 and use GeoTIFF 0.2 specifications to define a set of TIFF tags. These tags describe all cartographic information associated with the file. The average file size is 10 megabytes.
For information on how to cite USGS data plus guidance on usage restrictions,
please see our Data Citations and Use page at https://lta.cr.usgs.gov/citation.
Long Term Archive User Services
U.S. Geological Survey (USGS)
Earth Resources Observation and Science (EROS) Center
47914 252nd Street
Sioux Falls, SD 57198-0001
Phone Number: 605-594-6151
Toll Free: 800-252-4547
Business Hours: Monday thru Friday, 8:00 a.m. to 4:00 p.m., Central Time