This interface was created by the National Geologic Map Database project (NGMDB), in support of the topographic mapping program, managed by the USGS National Geospatial Program (NGP). TopoView shows the many and varied older maps of each area, and so is especially useful for historical purposes-for example, the names of some natural and cultural features have changed over time, and the historical names can be found on many of these topographic maps. The most current map of each area is available from The National Map. As the years passed, the USGS produced new map versions of each area. This mapping was done at different levels of detail, in order to support various land use and other purposes. In 1879, the USGS began to map the Nation's topography.
TopoView highlights one of the USGS's most important and useful products, the topographic map.
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