US GOS: Geospatial One Stop (a.k.a. geodata.gov)
geodata.gov is a geographic information system (GIS) portal, also known as the Geospatial One-Stop (GOS), that serves as a public gateway for improving access to geospatial information and data under the Geospatial One-Stop E-Government initiative. Not all data files are available for downloading.
National Atlas: Map Layers Warehouse
One of the best US government data download sites -
this site collects GIS data from various US
Federal agencies, and they are organized quite well.
Census Bureau: Maps and Cartographic Resources
Most data are created based on the Census Bureau's TIGER data - Various TIGER
base data are available from the Census Bureau's website, including
TIGER *raw* streets and boundary files. Check also ESRI's
CensusWatch website to get more TIGER base files.
DEM (10m, 30m, 1km), high resolution aerial photographs, and various small scale
data layers (such as transportation data) are available for downloading from
this Interactive mapping site.
Tip1: Make sure to turn off "pop-up
window blocker" of your web browser first.
Tip2: Zoom in the area of your interest, click "Download" tab on the right (default
is "Display" tab), and check on the layers that you wish to download then use the "Downloads" tools on the
left to select the area - wait for a minute or so to get the extracted data ready
Tip3: There is a limit on amount of data that you can download at once - you may
need to download data piece by piece depending on data type.
US Geological Survey: General Digital Data
USGS is one of the largest and most active GIS data
producers in the world! Here is a list of general digital data that they
US Geological Survey: Water Resources Data
Rich amount of water related GIS data are available from this site - see the full
list of water GIS datasets.
US Geological Survey: GEODE, GEO-DATA Explorer
USGS's data tool to access, view and download information from databases containing broad spectrum of data produced by the USGS and other government agencies.
US Dept. of Agriculture: NRCS: Geospatial Data Gateway
The Geospatial Data Gateway or Geo-Data Gateway provides easy and consistent access to natural resource data, including a variety of raster data, including aerial photographs. Users can search for available data by geographic area or by theme, and also view and download the data via FTP, or by ordering data media, such as CD.
US Dept. of Agriculture, NRCS: Natural Resources Conservation Service
USDA's Natural Resources Conservation Service produces a wonderful soil survey
data. For example, STATSGO (generalized, small-scale soil data) and
resolution, large-scale soil data). Download the detailed soil survey data,
SSURGO at Soil Data
EPA: Environmental Protection Agency
EPA used to release a very comprehensive & read-to-use GIS dataset plus
software, called BASINS, but now it is kind of hard to find a complete dataset
from EPA - you may want to get the data from other various agencies, such as
USGS, Water Resources Data site. Latest BASINS is available from our collection
and also from here, BASINS.
BTS: Bureau of Transportation Statistics - Mapping Center
Various types of transportation related datasets are available for downloading
from this site. For more information on BTS dataset in general, visit their
HUD: Dept of Housing and Urban Development
This site has links to
downloadable datasets and also interactive mapping
site (EGIS) which enables users to download some
of updated HUD specific data, such as assisted housing. User Hint: zoom-in well
in order to download detailed data - some data layers may not be seen unless you
zoom in enough.
FCC: Federal Communication Commission
FCC also produces several interesting GIS data files.
US Fish and Wildlife Services
National wildlife GIS data sets - great site for environmental researchers.
US Dept of Interior: National Park Service
National park resources are also available for GIS analysis - data are organized
by state, nice.
BLM: Bureau of Land Management
A collection of BLM GIS data distribution sites.
CDC: Center for Disease Control and Prevention
Resources for creating public health maps - good start for public health GIS
anlaysis! Epi Info is GIS freeware developed by CDC specifically for
epidemiologic spatial analysis - this freeware has been around for years - not
sure how much of its functionality was updated..
NOAA: National Oceanic and Atmospheric Administration
NOAA's geophysical data center - it seems to me that there are so many datasets
available from this point that I haven't explored much yet..
Georeferenced topogarphic maps and aerial photographs (DOQ) are available for
downloading (be sure to download a world file for each map/photo - which keeps
the georeferencing information.)
National Map: Interactive Mapping Site
Interactive mapping site by collaborative efforts among Federal and local
government - some
vector data are available for downloading, but just a few..
USGS Seamless Data Distribution System
Viewable and downlodable high resolution Aerial Photos for U.S. urban areas.
High resolution satellite imagery is available for the most of urban areas.
Click "Satellite" or "Hybrid" to see the orthoimagery, not
Microsoft Virtual Earth
Microsoft version of "Google Maps" - MSN Virtual Earth is a new Microsoft geo-spatial web site that integrates MSN Search, MapPoint Maps and Directions, and Microsoft
TerraServer-USA into a single application. When panning and searching within Virtual Earth, you can choose to see (1) road map only, (2) aerial image only, or (3) road map overlaid over aerial imagery.