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NOS Data Explorer - http://www.noaa.gov
Offers interactive mapping tools that allow users to locate NOS products in any area in the United States and its territories through a metadata catalog. |
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GeoNames - http://www.geonames.org/
A worldwide geographical database with a search function, browsable maps, and downloadable data files available free under a Creative Commons attribution license. |
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USGS Geography - http://geography.usgs.gov/
National mapping information from the U.S. Geological Survey. A good place to start the search for many kinds of GIS data. |
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Tele Atlas - http://www.teleatlas.com/
Compiler of digital maps and dynamic content used by essential navigation and location-based services. |
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Digital Chart of the World - http://www.maproom.psu.edu/dcw/
Download the boundaries and layers of different countries, in Arc/INFO export format. |