The U.S. Geological Survey (USGS) has been the primary civilian mapping agency of the United States since 1879. The best known USGS maps are the 1:24,000-scale topographic maps, also known as 7.5-minute quadrangles.
Download all dates and scales of USGS topographic maps free of charge from the following applications or order paper copies of all dates through the USGS Store. This includes both current US Topo maps (computer generated every 3 years since 2009) and Historical topographic maps (produced by hand until 2009). Most applications have an option for toggling on map indices showing an outline of all the maps, though you must zoom in to see the lines:
Map Locator on the USGS Store -- Search and download free digital maps in GeoPDF format or order paper maps. This is the only USGS site for ordering paper maps.
TopoView -- The largest selection of digital options. Download free digital maps in GeoPDF, GeoTIFF, JPG, and KMZ formats.
- Video lesson for using the Map Locator
- Video lesson for using TopoView
- USGS Historical Topographic Map Explorer (USGS & esri)
- Topographic Map Symbols