U.S. Geological Survey: a History of the National Program for Topographic Mapping (1884–2009) and Continuing Innovation into the Future.

• Topographic maps became a signature product of the USGS because the public found them — then and now — to be a critical and versatile tool for viewing the nation's vast landscape.
• From the 1880's until the advent of computers and geographic information system (GIS) software, topographic maps served as the essential instrument for the integration and analysis of place-based information.
• In the last quarter-century, advancing technologies have transformed topographic mapping science from the printed product to digital data and on-line based applications.
• Along with highlighting a legacy of 125 years of topographic mapping, the National Geospatial Program of the USGS is proud to release a new type of digital topographic map and the new interactive viewer for The National Map.