Building National Spatial Data Infrastructures

Scanning and georeferencing USGS topographic map collection

—Gregory Allord, U. S. Geological Survey

The U. S. Geological Survey (USGS) has published more than a quarter of a million different editions of topographic maps of the USA during the past 125 years. Copies of these historic maps are found in numerous libraries but the most complete collection known to exist is in the map library in the headquarters of the USGS, located in Reston, Virginia. Currently there is a common expectation everything of value, or required for reference and research, needs to be available through the Internet. The USGS has a continuing commitment to supply topographic maps to the Nation and recognizes its responsibility as custodians of its historic topographic map collection. This presentation describes the process underway to scan all topographic maps in the Reston Library. All maps will be accessible through the Web in either GeoTIFF and GeoPDF format. This discussion includes metadata captured and technical processes developed to spatially reference maps.