U.S. Department of the Interior

U.S. Geological Survey

Fact Sheet 2011–3042

April 2011

The National Map

National Geospatial Program Mission

The National Geospatial Program:

•	 Organizes, maintains, publishes, and disseminates the 

geospatial baseline of the Nation’s topography, natural 

landscape, and built environment through The National Map,

a set of basic geospatial information provided as a variety of 

products and services

•	 Fosters a general understanding of broad geographic patterns, 

trends, and conditions through The National Atlas of the United 

States of America®

•	 Increases the efficiency of the Nation’s geospatial community 

by improving communications about geospatial data, products, 

services, projects, needs, standards, and best practices

Introduction

The National Map comprises a variety of products and services 

that provide the Nation with access to base geospatial information 

to describe the landscape of the United States and its territories. The 

National Map (http://nationalmap.gov/) supports data download, 

digital and print versions of topographic maps, geospatial data 

services, and online viewing. Customers can use geospatial data and

maps to enhance their recreational experience, make life-saving decisions, support their scientific missions, and for countless other activities. Nationally consistent geospatial data from The National Map

enable better policy and land management decisions and the effective 

enforcement of regulatory responsibilities.

The National Geospatial Program (http://www.usgs.gov/

ngpo/) of the U.S. Geological Survey (USGS) manages The 

National Map. Partners and other organizations produce and 

maintain a vast array of high-quality geospatial data. A significant 

objective of the National Geospatial Program (NGP), through the 

Partnership Network (http://liaisons.usgs.gov/geospatial/), is 

to leverage these assets through mutually beneficial partnerships 

that ensure the ongoing availability of current data consistent with 

National Spatial Data Infrastructure (NSDI) principles.

The National Map Products and Services

The National Map embodies 11 primary products and services and numerous applications and ancillary services.

Data Products and Online Services

Boundaries

U.S. Bureau of Land Management

U.S. Census Bureau

U.S. Department of State

Elevation

U.S. Geological Survey

Geographic names

U.S. Geological Survey

Hydrography

U.S. Geological Survey

Land cover

U.S. Geological Survey

Orthoimagery

U.S. Geological Survey

Structures

General Services Administration

Transportation

U.S. Department of Transportation

Figure 1. Eight base layers of The National Map and associated Office of 

Management and Budget Circular A–16 thematic lead agencies.

The geospatial data available from The National Map include 

boundaries, elevation, geographic names, hydrography, land 

cover, orthoimagery, structures, and transportation. The Office of 

Management and Budget (OMB) has designated the USGS as the 

lead or colead agency (fig. 1) under Circular A–16 for elevation, 

geographic names, hydrography, land cover, and orthoimagery. Web 

viewing and download services are available for each of the eight 

data layers.

Boundaries (Government Units) Dataset.—The boundary 

data layer represents major civil areas including States, counties, 

Federal and Native American lands, and incorporated locales such 

as cities and towns. These data are useful for understanding the 

extent of jurisdictional or administrative areas for a wide range of 

applications, including demographics, natural disaster response, 

recreational activities such as hiking and backpacking, or resource 

management. The USGS obtains incorporated, unincorporated, 

county, State, and Native American area boundaries from U.S. 

Census data releases annually. Federal land boundaries are obtained 

from the Bureau of Land Management or directly from the source 

Federal agency if appropriate. The boundary data obtained from 

the source agency are transformed to a common data model to be 

rehosted and served from The National Map.

National Elevation Dataset.—The National Elevation Dataset 

(NED) is a seamless raster image dataset at multiple resolutions. NED 

data are available at 1-arc-second [30-meter (m)] resolution for all the 

conterminous United States, with 92 percent coverage at 1⁄3-arc-second (10-m) resolution and 12 percent coverage at 1/9-arc-second (3-m) 

resolution. Partnerships with a wide variety of Federal, State, and 

local cooperators to acquire higher resolution elevation data, primarily from light detection and ranging (lidar) sources, are the principal 

means used to continually improve the NED. While significant areas 

of new, higher resolution elevation data are being acquired, NED 

resolution for Alaska is primarily 2 arc-seconds (60 m).

Geographic Names Dataset.—The USGS maintains the 

Geographic Names Information System (GNIS), which is the 

authoritative database of official U.S. geographic names and is 

developed in cooperation with the U.S. Board on Geographic 

Names (BGN) (http://geonames.usgs.gov/). The NGP serves as 

the executive secretariat for the BGN, which is a Federal interagency body empowered by Public Law 80–242 (61 Stat. 456) 

to approve and issue standard geographic names for use on all 

material (data files, documents, maps, and reports) published by the 

Federal Government and its contractors. These geographic names 

include cultural and physical features, such as bays, hospitals, 
mountains, populated places, and valleys. The GNIS does not contain road or street names, nor does it define the extent of features; 

however, the GNIS contains attributes to help determine the relative extent of features.

National Hydrography Dataset.—The National Hydrography 

Dataset (NHD) provides mapping coverage of the surface waters 

of the United States consisting of 7.5 million miles of rivers and 

streams and 6.5 million lakes and ponds. The NHD provides a 

complete network that supports the analysis of any type of movement (for example, effluent dispersion, navigation, and sediment 

transport) by surface waters. Stewardship support services and 

extensive training are provided to partners interested in assisting in 

the maintenance of the NHD. The NHDPlus, developed by the U.S. 

Environmental Protection Agency, extends the power of the NHD 

by integrating additional geospatial data to generate drainage areas, 

flow velocity estimates, and flow volume.

National Land Cover Database.—The National Land Cover 

Database (NLCD) 2001 provides consistent land cover data for all 

50 States and a data framework that allows flexibility in developing 

and applying each independent data component to a wide variety of 

applications. Components in the database include normalized imagery for three time periods per Landsat path or row; ancillary data, 

including 30-m NED data derived into aspect, slope, and slope 

position; per-pixel estimates of percent imperviousness and percent 

tree canopy; 16 classes of land cover data derived from the imagery, ancillary data, and derivatives; and classification rules, confidence estimates, and metadata from the land cover classification. 

The NLCD was developed using a mapping zone approach, with 

more than 60 zones in the continental United States and Alaska. 

NLCD 2006, which was released in February 2011, quantifies land 

cover and land cover change between 2001 and 2006 and provides 

an updated version of NLCD 2001 land cover and imperviousness.

Orthoimagery Dataset.—Through cooperative partnerships, 

the USGS acquires and disseminates high-resolution digital orthoimagery data that have the accuracy and reliability of a base map. 

The resolution of the imagery in the USGS digital orthoimagery 

dataset varies from 1 m to 1 foot or finer. The USGS relies primarily on its partnership with the U.S. Department of Agriculture 

National Agriculture Imagery Program for 1-m-resolution, leaf-on 

imagery acquired on a 3-year cycle. Higher resolution data are 

obtained in partnership with the National Geospatial-Intelligence 

Agency (NGA), State, local, and tribal partners.

Structures Dataset.—USGS data portray selected structures 

data, including the function, name, location, and physical form 

from best available sources. Structures data support disaster planning and response and homeland security organizations and topographic mapping and resource planning needs. Structures data are 

acquired through partnerships with Federal and State entities. The 

USGS integrates structure data with the names data from the GNIS. 

The reconciled content is loaded into The National Map database 

and thus, Federal agencies and State entities have a common base 

for operating activities and a shared baseline for exchanging transactional data updates.

Transportation Dataset.—Transportation data consist of 

airports, railroads, roads, and other features associated with the 

transportation of people or commerce. The data include the address 

ranges, classification, location, and name or route designator for 

most roads. Transportation data support mapping and geographic 

analysis (such as for disaster planning and response). The National 

Map Viewer (http://viewer.nationalmap.gov/viewer/) features 

U.S. Census Bureau, Federal Aviation Administration, and U.S. 

Forest Service transportation data that can be downloaded, as well 

as road data as a layer that can be viewed but cannot be downloaded because they are derived from a commercial road dataset.

Map Products and Online Services

In 1879, the USGS was entrusted with the responsibility for 

mapping the country and has been the primary civilian mapping 

agency of the United States ever since. More than 200,000 USGS 

topographic maps have been published in paper form in scales 

primarily ranging from 1:20,000 to 1:250,000. The best known 

USGS maps are the 1:24,000-scale topographic maps, also known 

as 7.5-minute quadrangles. The 7.5-minute map series was officially 

completed in 1992, and only minor revisions have been made to 

the printed product in recent years. While the NGP is converting 

all the historic topographic map products to a digital format, hard 

copy maps are available for sale through the online USGS Store 

(http://store.usgs.gov/) and business partner retailers. The NGP 

began releasing digital topographic (US Topo) maps in October 

2009.

Digital Topographic Maps.—US Topo maps (fig. 2) can be 

downloaded for free from the USGS Store or The National Map

Viewer. The output of US Topo (http://nationalmap.gov/ustopo/

index.html) is a georeferenced map in GeoPDF format that has the 

look and feel of the historic 1:24,000-scale topographic map but 

includes slightly different content in digital format. As of 2011, 

37,500 US Topo maps have been released that include elevation 

contours, geographic names, hydrography, orthoimagery, and roads. 

As many as 100 US Topo maps are produced daily, whereas each 

historic 1:24,000-scale topographic map took 5 years to complete. 

The NGP is working on plans, procedures, standards, and performance criteria to meet the goal of updating US Topo maps on a 

3-year cycle, using available new data and including additional 

base layers when data content meets specified standards and levels 

of completeness.

Historic Topographic Maps.—All scales and editions of the 

maps published by the USGS since the inception of the topographic 

mapping program in 1884 are being scanned and made available 

in GeoPDF and GeoTIFF formats. As physical and cultural features changed over time, the topographic maps were updated and 

revised, and new editions were printed. These maps are often useful 

to environmentalists, genealogists, historians, scientists, and others 

researching a particular geographic location. This georeferenced, 

high-resolution scanning effort serves the dual purpose of creating 

a master catalog and digital archive of the irreplaceable collection 

of topographic maps in the USGS Reston Map Library as well as 

making the maps available for viewing and download from The 

National Map Viewer.

The National Map Viewer and Data Access.—The online 

user interface of The National Map is the Viewer (fig. 3), which 

allows a user to interactively view National Map data as a map, 

customize the view, print a map, and download the data for use 

in geographic information systems (GIS). The Viewer provides 

public access to high-quality, integrated National Map data from 

Federal, State, local, and tribal partners. Map tools allow the user 

to navigate the map (pan and zoom), identify features, and perform 

queries and other functions, such as take measurements and spot 

heights, get coordinates, and create export annotations. The Viewer 

was developed in partnership with the NGA and other entities. 

Unlike many others, the Viewer allows geospatial data to be downloaded directly or viewed with Open Geospatial Consortium (OGC) 

Web mapping services (WMS) and keyhole markup language 

(KML). Partner Web mapping services that are registered in the 

Geospatial One-Stop (GOS) portal as online geospatial services are 

also available to overlay onto The National Map base map.

The National Map Supporting Activities

There are other activities within the NGP that provide significant support to The National Map—geospatial technical operations, partnership network, geospatial research, and emergency 

operations.

Figure 2 (facing page). US Topo map for the Coffeyville East, Kans., 

quadrangle.

Geospatial technical operations efforts by the National Geospatial Technical Operations Center (NGTOC) (http://ngtoc.usgs.gov/) 

and the Earth Resources Observation Science (EROS) Center 

(http://eros.usgs.gov/) focus on developing and enhancing the usefulness of geospatial products and services; acquiring new geospatial 

data; assessing the geospatial data for accuracy, quality, and integration into nationwide datasets; archiving of raster and vector imagery; 

and improving public access to the geospatial data through online 

viewing and data downloading. NGTOC and EROS also perform 

research and development into new processes and technology in the 

implementation of The National Map, and one of their most critical 

roles is providing technical services to assist partners in the acquisition and maintenance of geospatial data that become part of The 

National Map. Finally, NGTOC and EROS develop and provide 

access to National Map products such as US Topo.

Partnerships provide significant cost savings, reduce 

redundancy in geospatial data acquisition and stewardship, and ensure availability of common base data to a broad 

range of users and applications. NGP’s Partnership Network 

(http://liaisons.usgs.gov/geospatial/) comprises headquarters 

liaisons, who coordinate with Federal agencies and national 

organizations, and State-based USGS geospatial liaisons, who are 

distributed across the Nation to coordinate efforts of the USGS and 

other Federal entities with State, local, and tribal groups. Liaisons 

work with these organizations to identify geospatial data requirements and standards, evaluate partnership opportunities, develop 

agreements, participate in State, regional, and local geospatial 

data councils, and provide outreach to user communities. Many of 

these organizations produce and maintain a vast array of current, 

accurate geospatial data. As a result, a large majority of data in The 

National Map is the product of jointly funded partnership agreements aligned with the goals of the NGP.

Geospatial research is conducted by the Center of 

Excellence for Geospatial Information Science (CEGIS) 

(http://cegis.usgs.gov/), which identifies and collaborates on 

geographic information science research issues of national importance. CEGIS basic research activities are guided by the published 

recommendations of the National Academy of Sciences and priorities established by the NGP management team based on long-term 

program direction and goals. Most CEGIS basic research efforts are 

in support of The National Map, but also include investigation of 

emerging technologies (such as the semantic Web and social media) 

and their effects on the NSDI and the emerging geospatial Web.

The Emergency Operations Office (http://www.usgs.gov/

emergency/) ensures coordination and rapid availability of The

National Map and other geospatial information for effective 

response to natural and other disasters by emergency responders, 

land and resource managers, and scientists. Procedures are established for acquisition, processing, and archiving of nonproprietary 

geospatial data; discovery, access, and delivery of data; and providing relevant geospatial products and services during and immediately 

after emergency events. These activities enable interdisciplinary 

integration of government assets to improve the value of data and 

services to responders and citizens in cases of emergency.

Relation of The National Map to The National Atlas of the 

United States of America®

The National Atlas of the United States of America®

(http://nationalatlas.gov/) uses datasets of a highly generalized 

framework from The National Map as the cartographic foundation for thousands of thematic maps. More than two dozen Federal 

agencies collaborate in the National Atlas to provide accurate, integrated, and reliable geospatial information about America’s natural 

and socioeconomic landscapes. Most National Atlas products are 

clearly designed for public use and include wall maps, innovative 

page-sized printable maps, and an interactive mapmaker for crafting custom maps. The National Atlas also includes multimedia articles about National Atlas maps as well as maps that illustrate how 

the Nation changes. All National Atlas data are fully documented 

and provided at no cost for download or direct use on the Internet. 

The data available from the National Atlas are provided at a scale 

where 1 inch on the map is roughly 16 miles; US Topo maps from 

The National Map are at a scale of 1 inch equals 2,000 feet.

Additional Information

Information about the National Geospatial Program is available 

at http://www.usgs.gov/ngpo/. For more information about 

The National Map, visit http://nationalmap.gov/ or e-mail 

nationalmap@usgs.gov.

By Larry J. Sugarbaker and William J. Carswell, Jr.

Figure 3. Screen capture from 

The National Map Viewer.