Gothos

A short list of sites with free GIS data layers, from global to local.

Global

• United Nations Environment Program - Geodata Portal. Click on “Advanced Search,” select “Geospatial Data Sets” under the first drop down box, and hit the red “Search” button. This will take you to a list of global or continental GIS files that you can download.
• Center for International Earth Science Information Network - Hosted by Columbia University, it contains links to datasets for the world, various countries, and the US.

Canada and Mexico

• GeoGratis - Canadian government GIS repository provided by the Earth Sciences Sector of Natural Resources Canada.
• GeoConnections - Portal to a wide range of Canadian geospatial data. Some resources are free, others must be purchased.
• Georeferenced Population Data Sets of Mexico - hosted by CIESIN.

Other Countries

• GIS datasets for individual countries can be difficult to find. One strategy is to look at the websites of various agencies in each country that produce maps and data to see if they provide online access. Visit UNESCO’s Map Agencies page for places to start looking.

United States

• 2007 TIGER Line Shapefiles - U.S. Census Bureau - extracts of the bureau’s TIGER Line files for several administrative (i.e. states, counties, metros, places, zip codes) areas in the US for 2000 and 2007.
• Cartographic Boundary Files - U.S. Census Bureau - generalized extracts of the bureau’s TIGER Line files for several administrative areas (i.e. states, counties, zip codes) and census (i.e. tracts, block groups, metros) areas in the US from 1990 and 2000.
• ESRI Census Watch - another free source for generalized TIGER line files from the makers of ArcGIS.
• National Historical Geographic Information System - the NHGIS is a project at the University of Minnesota that compiles and provides historical census boundaries and data for the United States from 1790 to 2000. New users must register, but there is no cost and downloads are free.
• GOS - Geospatial One Stop - a large US government sponsored geospatial depository for federal, state, and local datasets.
• USGS Seamless Data Distribution System - this federal agency provides imagery, digital topographic maps (DRGs), elevation data, and some boundary files.

State of New York

• CUGIR - Cornell University’s Geospatial Information Repository. They also compile data at the state, county, and local levels for NY State and they coordinate their activities with NYS GIS.
• NYS GIS Clearinghouse - a state government depository that compiles GIS data produced at the state, county, and local levels for New York State. Downloads are limited.
• NYS GIS - Digital Orthoimagery Direct - the NYS GIS page for imagery (orthophotos), tiles can be searched by county and year. Imagery for the five boroughs for the most current series (2000 - 2006) is only available by direct, special request. Imagery from the older series (1994-1999) is available for all areas.
• NY State Museum - has statewide layers for surface and bedrock geology.

State of New Jersey

• New Jersey Geographic Information Network - a clearinghouse for data produced at the state, county, and local level. The site includes interactive mapping, files for download, and a list of off-line resources.
• NJ Image Warehouse - The NJGIN page for imagery (orthophotos) downloadable by county or municipality, and by year (2002 or 1995).
• NJDEP GIS - Digital Data - the New Jersey Dept of Environmental Protection provides boundary files and features (environmental and administrative) at the state, county, and water

New York City

• BYTES of the BIG APPLE - the NYC Department of City Planning’s page has administrative and political boundaries, streets, transportation networks, shorelines, and tax parcels.
• DoITT - Services: GIS - the NYC Department of Information Technologies and Telecommunications has transportation networks, survey points, water bodies, building footprints, and open spaces.