We often take for granted the National Atlas and the online webmapping services provided – like the recently launched National Environmental Atlas. But did you also know that there’s a wealth of freely downloadable GIS data layers available from the site as well? Suitable as basemapping layers for apps at the National level, layers like county boundaries, time zones, congressional districts, Federal lands and many others (climate, environmental, Geology, Transport, Water) are found right here in the Raw Data download Section