The lower 48 states can be catergorized into eight physical regions.
Eight physical regions make up the contiguous United States. These regions are defined by their geographic characteristics, such as mountain ranges, plains and bodies of water. The regions span from west to east, each ranging in size from approximately 100 miles to nearly 1,500 miles.
The Pacific Coast Region stretches from the Canadian to Mexican border. It includes Washington, Oregon and California and begins at the Pacific Ocean and extends east, ranging from 100 to 150 miles inland. Prone to volcanic eruptions and earthquakes, the Pacific Coast is home to several densely populated cities, such as San Diego, Los Angeles, Seattle and Portland, Oregon.
Sierra Nevada and Cascade Mountains
The Sierra Nevada and Cascade Mountains Region is a narrow strip that begins at the Canadian border and runs throughout most of California. It includes the Cascade Mountains, which run from Canada to northern California and Sierra Nevada Mountains, which run along the California-Nevada border. The states included in the Sierra Nevada and Cascade Mountains region are Washington, Oregon and California.
The Great Basin runs from the Canadian to Mexican border and includes sections of Washington, Oregon, Idaho, Utah, California, Arizona and all of Nevada. This sparsely populated region is nestled between the Cascade and Sierra Nevada mountain ranges and the Rocky Mountains. It is characterized by valleys and deserts, such as Death Valley. Major cities within the Great Basin include Las Vegas, Phoenix and Salt Lake City.
Rocky Mountains and Plateaus
Portions of nine states make up the Rocky Mountains and Plateaus Range: Washington, Idaho, Montana, Wyoming, Utah, Colorado, Arizona, New Mexico and Texas. As the name implies, this region is characterized by the mountain chains and plateaus that make up the Rocky Mountains. Major cities within the sparsely populated Rocky Mountains and Plateaus Region include Denver; Santa Fe, New Mexico, and El Paso, Texas.
The Great Plains region stretches across portions of Montana, North Dakota, South Dakota, Wyoming, Nebraska, Colorado, Kansas, New Mexico, Oklahoma and Texas. The Great Plains and are characterized by mostly flat lands with some rolling hills. Major cities within this region include San Antonio, Dallas and Oklahoma City.
Mississippi River and Great Lakes
The Mississippi River and Great Lakes Region is the largest region, extending from the eastern regions of North Dakota, South Dakota, Nebraska, Kansas, Oklahoma and Texas to portions of Vermont, New York, Pennsylvania, Ohio, Kentucky, Tennessee, Alabama, Georgia and Florida. Other states included in this region include Minnesota, Iowa, Missouri, Arkansas, Louisiana, Wisconsin, Illinois, Mississippi, Michigan and Indiana. This area is characterized by mainly flat land with rolling hills in the Ozark Mountain region. The Mississippi River cuts through the middle of the region and the five Great Lakes mark the region’s northern border. Major cities in the Mississippi River and Great Lakes region include Chicago, Milwaukee, Minneapolis, Detroit, Indianapolis, Cincinnati and New Orleans.
The Appalachian Mountains Region stretches north from eastern Alabama to central Maine. It includes sections of Georgia, South Carolina, North Carolina, Virginia, Maryland, Pennsylvania, New York, Massachusetts, Vermont, New Hampshire and all of West Virginia. Named for the Appalachian Mountains, which makes up the spine of the region, the Appalachian Mountains Region also includes the Allegheny and Blue Ridge mountains. Major cities within this region include Atlanta, Charlotte, North Carolina, and Albany, New York.
Atlantic Coastal Plains
The Atlantic Coastal Plains stretches north from the central panhandle of Florida to the tip of Maine. It includes sections of Alabama, Georgia, South Carolina, North Carolina, Virginia, Maryland, Massachusetts and New Hampshire, and all of Delaware, Washington, D.C., Connecticut, New Jersey and Rhode Island. This heavily populated region is characterized as generally flat with marshlands in the south and hardwood forests in the north. Major cities include Boston, New York City, Baltimore and Miami.