What constitutes the United States? What are the official definitions?

Geographically (and as a general reference), the United States of America includes all areas considered to be under the sovereignty of the United States, but does not include leased areas.

On May 14, 1959, the U.S. Board on Geographic Names issued the following definitions based partially on the Alaska Omnibus Bill, which defined the Continental United States as "the 49 States on the North American Continent and the District of Columbia..." The Board reaffirmed these definitions on May 13, 1999.

United States: The 50 States and the District of Columbia.

Continental United States: The 49 States (including Alaska, excluding Hawaii) located on the continent of North America, and the District of Columbia.

Conterminous United States: The 48 States and the District of Columbia; that is, the United States prior to January 3, 1959 (Alaska Statehood), wholly filling an unbroken block of territory and excluding Alaska and Hawaii. Although the official reference applies the term "conterminous," many use the word "contiguous," which is almost synonymous and better known.

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Can I add new entries to the Geographic Names Information System for manmade and administrative features, such as churches, cemeteries, schools, shopping centers, etc.?

Suggested corrections and additions to the Geographic Names Information System (GNIS) data are accepted from any source for review. Upon validation, they will be committed to the database. For manmade and administrative features, submit the official name of the feature with its precise location in geographic coordinates (latitude/longitude), the...

Does the Geographic Names Information System Database contain entries for obsolete names and historical geographic features that no longer exist?

Yes, The Geographic Names Information System (GNIS) actively seeks names of features that no longer exist. The term "historical" as used in the GNIS specifically means that the feature no longer exists on the landscape. An abandoned ghost town, for example, still exists so it is not historical. Historical features have no reference to age, size,...

How many counties are in the United States?

There are 3,141 counties and county equivalents in the 50 States and the District of Columbia: 3,007 entities named "County" 16 Boroughs in Alaska 11 Census Areas in Alaska (for areas not organized into Boroughs by the State) 64 Parishes in Louisiana 42 Independent Cities (1 in Maryland, 1 in Missouri, 1 in Nevada, and the remainder in Virginia) 1...

What is the most common city/town name in the United States?

There are no official definitions of city, town, village, hamlet, neighborhood, etc. All named entities with human habitation are classified as Populated Place, including incorporated places (20 percent of the Nation's communities), unincorporated places (the majority), housing developments not yet incorporated, and neighborhoods within...

What are the official definitions of regions in the United States. For example, what is "the Midwest," "the South," or the “East Coast”?

No level of government has official designations for regions. The U.S. Board on Geographic Names , which is responsible by law for standardizing geographic name usage throughout the Federal government, is often asked for official names and boundaries of regions, but does not and cannot provide them. Regions are application-driven and highly...

How are U.S. states, territories, and commonwealths designated in the Geographic Names Information System?

Several categories with different meanings and requirements fall under the jurisdiction of the United States and are contained in the Geographic Names Information Sytem (GNIS) data. States and DC 50 States plus the Federal District known as District of Columbia Commonwealths Puerto Rico (Caribbean) Northern Marianas Islands (Pacific) (former Trust...

What is the Geographic Names Information System (GNIS)?

The Geographic Names Information System (GNIS) was developed by the U.S.Geological Survey (USGS) in cooperation with the U.S. Board on Geographic Names (BGN), which maintains cooperative working relationships with state names authorities to standardize geographic names. GNIS contains information about the official names for places, features, and...
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Date published: May 20, 2019

New Land Cover Maps Depict 15 Years of Change across America

Today, the U.S. Geological Survey (USGS) released the latest edition of the National Land Cover Database (NLCD) for the U.S. – the most comprehensive land cover database that the USGS has ever produced. The NLCD 2016 documents land cover change in the Lower 48 states from 2001 to 2016. During this 15-year period, 7.6 percent of the conterminous U.S. changed land cover at least once.

Date published: July 31, 2017

Mapping Public Lands in the United States

The Protected Areas Database of the United States (PAD-US) is the official inventory of public parks and other protected areas in all U.S. states and territories.

Date published: July 26, 2017

Volunteering to Map the Nation

As the USGS continues to celebrate “Mapping Month”, we again promote noteworthy contributors to The National Map Corps “crowdsourcing” project.

Date published: February 28, 2014

The National Map and National Atlas Merge

During this year, National Atlas of the United States and The National Map will transition into a combined single source for geospatial and cartographic information. This transformation is projected to streamline access to maps, data and information from the USGS National Geospatial Program (NGP). 

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Aquifers: Map of the Principal Aquifers of the United States
March 13, 2018

Aquifers: Map of the Principal Aquifers of the United States

Aquifers: Map of the Principal Aquifers of the United States

Photograph of the United States at Night
September 9, 2016

Photograph of the United States at Night

The importance of electric power is demonstrated by this view from space of lights across the continental United States at night. Credit: NASA

A map of the United States depicting ecoregion borders
February 21, 2008

A map of the United States depicting ecoregion borders

A map of the lower 48 states of the United States showing land cover overlayed with ecoregion boundaries.

AVHRR color mosaic of U.S., circa 1986
December 31, 1984

1984-1986 - AVHRR Mosaic of United States

AVHRR data were collected by the second antenna at the Center and provided daily global coverage.

Attribution: Land Resources
1974 Geologic Map of the United States.
December 31, 1974

1974 Geologic Map of the United States.

King and Beikman's 1974 Geologic Map of the United States.