e-ReferenceDesk's College and 50 State Learning Resource Guide

Find Online Colleges

Find Campus Colleges

US Geography: The Land

State Symbols

The United States is a nation in the Western Hemisphere. It consists of forty-eight contiguous states on the North American continent; Alaska, an enormous peninsula which forms the northwestern most part of North America, and Hawaii, an archipelago in the Pacific Ocean. It also holds several United States territories in the Pacific & Caribbean. The country shares land borders with Canada and Mexico and a water border with Russia.

Physiographic Regions

Physiographic Regions of the lower 48 US States

Geomorphic, or physiographic, regions are broad-scale subdivisions based on terrain texture, rock type and geologic structure and history

The image presented here shows the topographic textures and generalized geology (by age) from which the physical regions were synthesized

A physiographic province is a landform region, an area delineated according to similar terrain that has been shaped by a common geologic history.

There are eight distinct physiographic divisions within the continental United States. Each is composed of smaller physiographic areas called provinces and sections respectively.

Eight Distinct Physiographic Divisions

Laurentian Upland (area labeled 1) - part of the Canadian Shield that extends into the northern United States Great Lakes area.
Atlantic Plain (2 and 3) - the coastal regions of the eastern and southern parts includes the continental shelf, the Atlantic Coast and the Gulf Coast.
Appalachian Highlands (4-10) - lying on the eastern side of the United States, it includes the Appalachian Mountains, Adirondacks and New England province.
Interior Plains (11-13) - part of the interior contentintal United States, it includes much of what is called the Great Plains.
Interior Highlands (14 and 15)- also part of the interior contentintal United States, this division includes the Ozark Plateau.
Rocky Mountain System (16-19) - one branch of the Cordilleran system lying far inland in the western states.
Intermontane Plateaus (20-22) - also divided into the Columbia Plateau, the Colorado Plateau and the Basin and Range Province, it is a system of plateaus, basins, ranges and gorges between the Rocky and Pacific Mountain Systems. It is the setting for the Grand Canyon, the Great Basin and Death Valley.
Pacific Mountain System (23-25)- the coastal mountain ranges and features in the west coast of the United States.

Physiographic Regions of the lower 48 US States

LAURENTIAN UPLAND

Superior Upland

ATLANTIC PLAIN

Continental Shelf
Coastal Plain
- Embayed section
- Sea Island section
- Floridian section
- East Gulf Coastal Plain
- Mississippi Alluvial Plain
- West Gulf Coastal Plain

APPALACHIAN HIGHLANDS

Piedmont province
- Piedmont Upland
- Piedmont Lowlands
Blue Ridge province
- Northern section
- Southern section
Valley and Ridge province
- Tennessee section
- Middle section
- Hudson Valley
St. Lawrence Valley
- Champlain section
- Northern section
Appalachian Plateaus province
- Mohawk section
- Catskill section
- Southern New York section
- Allegheny Mountain section
- Kanawha section
- Cumberland Plateau section
- Cumberland Mountain section
New England Province
- Seaboard Lowland section
- New England Upland section
- White Mountain section
- Green Mountain section
- Taconic section
Adirondack province

INTERIOR PLAINS

Interior Low Plateaus
- Highland Rim section
- Lexington Plain
- Nashville Basin
Central Lowland
- Eastern Lake section
- Western Lake section
- Wisconsin Driftless section
- Till Plains
- Dissected Till Plains
- Osage Plains
Great Plains province
- Missouri Plateau, glaciated
- Missouri Plateau, unglaciated
- Black Hills
- High Plains
- Plains Border
- Colorado Piedmont
- Raton section
- Pecos Valley
- Edwards Plateau
- Central Texas section

INTERIOR HIGHLANDS

Ozark Plateaus
- Springfield-Salem plateaus
- Boston "Mountains"
Ouachita province
- Arkansas Valley
- Ouachita Mountains

ROCKY MOUNTAIN SYSTEM

Southern Rocky Mountains
Wyoming Basin
Middle Rocky Mountains
Northern Rocky Mountains

INTERMONTANE PLATEAUS

Columbia Plateau
- Walla Walla Plateau
- Blue Mountain section
- Payette section
- Snake River Plain
- Harney section
Colorado Plateaus
- High Plateaus of Utah
- Uinta Basin
- Canyon Lands
- Navajo section
- Grand Canyon section
- Datil section
Basin and Range province
- Great Basin
- Sonoran Desert
- Salton Trough
- Mexican Highland
- Sacramento section

PACIFIC MOUNTAIN SYSTEM

Cascade-Sierra Mountains
- Northern Cascade Mountains
- Middle Cascade Mountains
- Southern Cascade Mountains
- Sierra Nevada
Pacific Border province
- Puget Trough
- Olympic Mountains
- Oregon Coast Range
- Klamath Mountains
- California Trough
- California Coast Ranges
- Los Angeles Ranges
Lower California province

US Geography

General characteristics

Forty-eight of the States are in the single region between Canada and Mexico; this group is referred to, with varying precision and formality, as the continental or contiguous United States, and as the Lower 48. Alaska, which is not included in the term contiguous United States, is at the northwestern end of North America, separated from the Lower 48 by Canada. The State of Hawaii is an archipelago in the Pacific Ocean. The capital city, Washington, District of Columbia, is a federal district located on land donated by the state of Maryland.

(Virginia had also donated land, but it was returned in 1847.) The United States also have overseas territories.