The National Map
Published Topographic Maps The USGS was entrusted with the responsibility for mapping the country in 1879 and has been the primary civilian mapping agency of the United States ever since. The best known USGS maps are the 1:24,000-scale topographic maps, also known as 7.5-minute quadrangles. More than 55,000 7.5-minute maps were made to cover the 48 conterminous states. This is the only uniform map series that covers this area of the United States in considerable detail. The 7.5-minute map series was officially completed in 1991; only minor revisions have been made to the printed product in recent years as the program has moved to a digital format. The hard copy maps are still available for sale through the online USGS Store, http://store.usgs.gov/, and business partner retailers.
Scanned Topographic Maps This product line contains images produced by scanning current editions of published (printed) versions of USGS 7.5 minute series topographic maps. The resulting image files are converted to georeferenced GeoPDF's. These maps are downloadable from the new "Map Locator and Downloader" portal of the USGS Store found at: http://store.usgs.gov/.
Full coverage will be provided by scanning all topographic maps published by the USGS starting in 1879. These will be high-resolution and will include all map scales and every edition (date) published during the past almost 130 years. The images of these maps will deliver complete coverage for the entire area of the United States, as well as some territories. These maps, as they are completed beginning in 2009, will be added to The National Map for viewing and will also be downloadable through the USGS Store.