Maps and Mapping
How do I find, download, or order topographic maps?
What types of elevation datasets are available, what formats do they come in, and where can I download them?
What is a Digital Orthophoto Quadrangle (DOQ) or an orthoimage?
The USGS provides the mapping and digital geospatial foundation for the Nation.
What sources of vector data were used to create base maps in The National Map?
Vector data for small scales are from The National Map Small-Scale Collection , while medium to large scales are comprised of The National Map themes, including the National Hydrography Dataset (NHD) and Geographic Names Information System (GNIS) data. Other medium-to-large-scale vector features are from USGS edited versions of the U.S. Census Bureau's TIGER/Line data for Governmental Unit...
How can I download vector data from The National Map in bulk?
The USGS only offers vector downloads from The National Map in bulk by special request. For assistance, send an e-mail to tnm_help@usgs.gov and include your contact information, requested product, requested area, and download format.
What is the vertical accuracy of the 3D Elevation Program (3DEP) DEMs?
As of 2022, the absolute vertical accuracy of the 3D Elevation Program (3DEP) 1/3 arc-second seamless DEM product within the conterminous United States is approximately 0.82 meters root mean square error (RMSE), based on a comparison to almost 25,000 NOAA National Geodetic Survey OPUS points . Accuracy has improved from a RMSE of 1.55 meters tested in 2013, due to the addition of lidar projects...
What is the coverage of 3D Elevation Program (3DEP) DEMs?
Elevation products are summarized on our 3-D Elevation (3DEP) Products and Services website . View detailed availability maps (status graphics) through several sites: The National Map Download Client – Click “Show” below each elevation product Lidar Availability Viewer - Lidar point cloud only LidarExplorer – Lidar point cloud only DEM Availability Viewer - 1 meter DEMs only Learn more: What is...
What is the projection, horizontal datum, vertical datum, and resolution for a USGS digital elevation model (DEM)?
Projection : 3DEP DEMS have different projections/coordinate systems depending on the product: 1/3-, 1-, and 2-arc-second (also the discontinued 1/9-arc-second) DEMs are not projected. They are all in geographic coordinates (latitude/longitude). 5-meter DEMs (Alaska only) are Alaska Albers Equal Area. 1-meter DEMs are in Universal Transverse Mercator (UTM). Original Product Resolution (OPR) DEMs...
Is there a list of mountain peak elevations in the United States?
The USGS does not have specific data for current mountain peak elevations other than what was previously published in an Elevations and Distances in the United States booklet. To determine an approximate elevation at a specific point, use the spot elevation tool query in the in The National Map Viewer or search for features via the Geographic Names Information System (GNIS) Search Domestic...
How do I find the average elevation of a city, town, county, or other civil division?
Average (or mean) elevations for civil divisions are not available from the USGS. You can, however, find the elevation at the center of a civil division using the Geographic Names Information System (GNIS): Go to the GNIS Search Domestic Names . Select "Search Domestic Names" In the Name box, type the city, town, county, etc. name (for example, “Stanley,” “Richmond,” "Madison County") In the...
What is the difference between lidar data and a digital elevation model (DEM)?
Light detection and ranging (lidar ) data are collected from aircraft using sensors that detect the reflections of a pulsed laser beam. The reflections are recorded as millions of individual points, collectively called a “point cloud,” that represent the 3D positions of objects on the surface including buildings, vegetation, and the ground. Digital elevation models ( DEMs ) are one of many...
How do I report errors in 3D Elevation Program (3DEP) elevation data?
If you think you’ve found an error in USGS elevation data, please send an email to tnm_help@usgs.gov . We will add the reported information to our "Digital Elevation Model Issues" data log for further analysis and possible correction. Spikes, pits, seam-line anomalies, and other data errors are of concern to us. We are working to correct or minimize known issues, but it will take some time. Errors...
How can visually impaired individuals use The National Map viewer or download client?
The USGS is committed to making its websites accessible to all users in accordance with provisions of Section 508 of the Rehabilitation Act of 1973 (as amended in 1998). Currently, there is no technology capable of producing alternatives to dynamically generated geospatial images in The National Map viewer or download client that are accessible to visually impaired individuals, so compliance with...
What are the Terms of Use/Licensing for map services and data from The National Map?
Map services and data downloaded from The National Map are free and in the public domain. There are no restrictions; however, we request that the following acknowledgment statement of the originating agency be included in products and data derived from our map services when citing, copying, or reprinting: "Map services and data available from U.S. Geological Survey, National Geospatial Program."...
Where can I find a list of URLs for The National Map services?
See The National Map Services for a complete list of map service URLs. That includes available REST, WMS, WMTS (cached base maps only), WFS, WCS, and other service links. Learn more: Training videos for The National Map Products and Services The National Map Applications