This page is dynamic. Resources are constantly evaluated and added to it or removed.
ArcGIS Online - a cloud-based, collaborative content management system for maps, apps, data, and other geographic information.
Atlas of Historical County Boundaries - presents in maps and text complete data about the creation and all subsequent changes (dated to the day) in the size, shape, and location of every county in the fifty United States and the District of Columbia. It also includes non-county areas, unsuccessful authorizations for new counties, changes in county names and organization, and the temporary attachments of non-county areas and unorganized counties to fully functioning counties. The content includes interactive maps, shapefiles and metadata.
DIVA-GIS - free computer program for mapping and geographic data analysis. Select and download free geographic (GIS) data for any country in the world. Boundaries, inland water, roads, railroads, elevation, land cover, population, etc. Download free spatial data: country level, global level, global climate data, species occurrence data, crop (genebank) collection data, etc.
Earth Explorer - research and download historical USGS data, such as Digital Orthophoto Quadrangles and Digital Line Graphs, or to access lidar point cloud data.
GIS Cloud - create, upload, author, publish, and share your spatial data in the Cloud; view and access maps and data. Requires an account. Service is free for non-professional use.
GIS Internet Resources - a portal created and managed by the U.S. Army geospatial Center, Alexandria, VA. provide pointers to GIS companies, associations, and government web pages as well as sources of software, data, publications, and services. There is a disclaimer that the information does not reflect use or endorsement by the U.S. Government.
GIS Services, University of Oregon - a variety of base and thematic data available for download for the entire state of Oregon; links to online sources for GIS data.
GeoCommons - the public community of GeoIQ users who are building an open repository of data and maps for the world. The GeoIQ platform includes a large number of features that empower you to easily access, visualize and analyze your data. You can watch any of our videos to learn more, or just sign up for free to get started building your own maps.
GeoNetwork - a geospatial portal created and managed by the World Food and Agriculture Organization.
Geospatial Modeling - provides you with a suite of analysis and modeling tools, ranging from small 'building blocks' that you can use to construct a sophisticated work-flow, to completely self-contained analysis programs; also uses the powerful open source software R as the statistical engine to drive some of the analysis tools. GME incorporates most of the functionality of its predecessor, HawthsTools, but with some important improvements.
Gridded Population of the World - hosted by CIESIN at Columbia University. Provides globally consistent and spatially explicit human population information and data; gridded, or raster, data product that renders global population data at the scale and extent required to demonstrate the spatial relationship of human populations and the environment across the globe. The native grid cell resolution is 2.5 arc-minutes, or ~5km at the equator. Population data estimates are provided for 1990, 1995, and 2000, and projected to 2005, 2010, and 2015. There is also an extensive map collection that includes population density and sub-national administrative boundary maps at country, continental, and global levels.
Historical GIS for European Integration Studies - historical cartographic data from different sources in GIS format. The data ranges from the early 1800s to present on a variety of subjects or topics.
International Livestock Research Institute - extensive range of spatial data layers related to livestock as well as general topics such as human population density, climate and infrastructure.Available shapefiles cover mainly Africa and South Asia.
National Historical Geographic Information System - provides, free of charge, aggregate census data and GIS-compatible boundary files for the United States between 1790 and 2010. Users must create a free account in order to download data.
The National Map Viewer and Download Platform - visualize, inspect, and download the United States Geological Survey’s most current topographic base map data and products for free. Data include: Elevation, Orthoimagery, Hydrography, Geographic Names, Boundaries, Transportation, Structures, and Land Cover, while products include: US Topo and Historical Topo Maps. The National Map Viewer also allows visualization and identification queries (but not downloads) of other featured data, to include Ecosystems, Protected Areas, Gap Analysis Program Land Cover, Hazards, Weather, Wetlands, Public Land Survey System, and National Park Service Boundaries.
OpenStreetMap - a free worldwide map. The data is free to download and use under its open license.
SimplyMap - an award-winning, web-based mapping application that changes the way you use and interact with complex data. SimplyMap enables non-technical and advanced users to quickly create professional thematic maps and reports using powerful demographic, business, and marketing data. Restricted to members of the Cornell community.
ThinkQuest - a collection of free temporal GIS data for anybody to download to make their own historic maps.
VDS Technologies - provides free downloadable shapefiles for most of the world.