Digital Spatial Data
The Map Library has a growing collection of digital
data that includes base reference data and
more specific data for specific themes and places,
including raster and vector data.
Digital Raster Graphics (DRGs): Scanned and georeferenced USGS topographic maps of Colorado at 1:250,000, 1:100,000, and 1:24,000.
Digital Orthophoto Quarter Quads (DOQQs): USGS aerial photographs of the Front Range that have been scanned, georeferenced, and rectified to remove distortion at 1:24,000.
Digital Elevation Models (DEMs): The National Elevation Dataset is seamless 10 meter and 30 meter DEMs for the entire United States.
Global GIS Database: Reference data for the world at 1:1 million. Includes administrative boundaries, base geology, hydrology, roads, population density and more.
ESRI Data & Maps: Reference data for the world, scales vary. Includes global DEM and shaded relief images, administrative boundaries, base geology, hydrology, roads, population density, and U.S. transportation data, recreation areas, data from the National Atlas, and more.
TerraserverUSA: (http://www.terraserver-usa.com/) USGS DRGs and DOQQs, including high-resolution orthoimagery of urban areas. Free Internet resource. Download using the ArcGIS Terraserver Toolbar for full resolution.
Digital Line Graphs (DLGs), the National Hydrography
Dataset (NHD), and many other datasets produced by
the USGS can be downloaded for free from the USGS web site.
Other GIS Data in the Map Library
The federal government and many state and regional
governments publish GIS data online and on CD-ROM.
The Library owns or has cataloged much of this data
and the Chinook
Library Catalog is the best place to start looking
for specific data sets.
The Map Library's Links & Web Resources Online
GIS Data page points to authoritative
web sites that serve out GIS data.
