BASE MAPS

Geo.data.gov

geodata.gov is a web-based portal for one-stop access to maps, data and other geospatial services that will simplify the ability of all levels of government and citizens to find geospatial data and learn more about geospatial projects underway.geodata.gov is part of the Geospatial One-Stop initia

ArcWorld

This database contains extensive cartographicbasemap data for the world at a scale of 1:3 million.It includes cartographic, index, and statistical information suitablefor a wide range of mapping, reference, and analytical application