“U.S. Geological Survey (USGS) topographic maps have accurately portrayed the complex geography of the Nation. The USGS is the largest producer of printed topographic maps, and, prior to 2009, USGS topographic maps were created using traditional cartographic methods and printed using the lithographic printing process.

Because historical maps are stored in a limited number of collections and are not readily available, the USGS National Geospatial Program (NGP) is converting these historical printed topographic quadrangles to an electronic format (GeoPDF). This scanning and processing effort serves the dual purpose of creating a master catalog and digital archive copies of the irreplaceable collection of topographic maps in the USGS Reston Map Library as well as making the maps available for viewing and download from the USGS Store.

The loading of the more than 200,000 historical maps to the USGS Store has begun, and there are currently 90,000 GeoPDF maps available to download and view. The number of available files, at different published scales, will continue to grow throughout the next year.”