GADM is a spatial database of the location of the world's administrative areas (or adminstrative boundaries) for use in GIS and similar software. Administrative areas in this database are countries and lower level subdivisions such as states, provinces, departments, etc.

The Advanced Weather Interactive Processing System (AWIPS) uses shapefiles for base maps in the system. A widely used common subset of these shapefiles have been made available for use by NWS partners. These shapefiles contain boundaries of areas used by NWS for forecasts and warnings as well as map backgrounds

This is a public domain map dataset available at 1:10m, 1:50m, and 1:110 million scales from North American Cartographic Information Society. It features tightly integrated vector and raster data of physical and cultural features.