Topic: Geography of the United States (2024)

The United States is the third largest country in the world, with one of the most diverse topographies and climates of any region. The mainland stretches across the breadth of North America; it has land borders with Canada to the north and Mexico to the south, and coastlines along the Atlantic and Pacific Oceans, as well as the Gulf of Mexico. The mainland is made up of 48 contiguous states, with Alaska to the northwest (connected to the mainland by British Columbia, Canada), and Hawaii 2,200 miles southwest in the Pacific Ocean. The U.S. also has 14 overseas territories in the Pacific and Caribbean – five of these are permanently inhabited, the largest of which is Puerto Rico. There is a great deal of variation in the terrain and geographical features of the contiguous United States, but there are some broad and common traits across the western, central, and eastern regions of the country. The variety and diversity of geographical features in the United States also creates abundant opportunities for agriculture, energy, and recreation for the American population.

Measurements

Measuring from its furthest points, the contiguous United States is approximately 2,800 miles from east to west, and 1,650 miles from north to south. The total area of the U.S. and its territories is over 3.8 million square miles. The largest state in the contiguous U.S. is Texas, while Rhode Island is the smallest. Alaska is the largest state overall, at roughly 2.5 times the size of Texas, and if it was an independent country it would be among the 20 largest in the world. Almost 270,000 square miles of U.S. territory (seven percent of the total area) is made up of water area, such as rivers, lakes, and inlets, as well as coastal territory – when water area is removed from the total area, the U.S. falls behind China to become the fourth largest country in the world. The northern border with Canada is approximately 5,525 miles long, and is the longest international border, while the southern border with Mexico is 1,933 miles long and is the most frequently crossed border in the world.

West

The west is dominated by mountainous, forested, and desert regions, which extend into Canada and Mexico. The largest mountain ranges are the Rocky Mountains, Sierra Nevada, and Cascade Range, although there are a number of smaller ranges and deserts between the Rockies and Pacific Coast. Most of the deserts in the United States are found in the west and southwest, the majority of which are cold deserts - these have formed as clouds and humid air are prevented from travelling inland by high elevation, forming rain shadows, which are areas of significantly reduced rainfall – because of this, western states have the lowest average rainfall in the country. The largest of these is the Great Basin Desert, which overlaps with several other hot deserts such as the Mojave and Sonoran to form the Basin and Range Province, which covers much of the southwest – however, the largest individual desert in North America, the Chihuahuan, is a hot desert, and is found overlapping with the Mexican border.

The arid conditions in the southwest are home to some of the country’s most spectacular natural phenomenon, such as the Grand Canyon, Bryce Canyon, and Death Valley. Further north and along the coast, the terrain is much more forested – of the United States’ 154 protected national forests, the 30 largest are all found in the west or Alaska. Additionally, the U.S. has 63 national parks, which are protected for their natural beauty, wildlife, and local significance, and these have a higher distribution in the west. The most well-known of these is Yellowstone National Park, famous for its geothermal features, although the four largest national parks are in Alaska, while the most visited is the Great Smoky Mountains National Park in the Appalachians in the eastern part of the country. Colorado is also the most renowned state for its winter sports opportunities, although there are numerous other mountainous regions in the west and northeast with notable ski resorts.

Alaska and Hawaii are often categorized as belonging to the western region of the country, and these represent some of the most extreme contrasts in U.S. geography. Alaska is known for its vast wilderness and cold climate, whereas Hawaii is known for its tropical climate, volcanoes, and touristic appeal. The highest mountain in the U.S. is Denali, Alaska, however Mauna Kea, Hawaii is sometimes considered the tallest mountain in the world, as its base begins well below sea level but it has a total height over 33,000 feet (roughly 4,500 taller than Mount Everest).

Central

To the east of the Rockies is the Plains region – this is a large stretch of relatively flat terrain that runs the length of the country into both Canada and Mexico, with large parts covering or extending into at least 14 states. This area covers much of the Midwest region, and these are among the most sparsely populated states on the mainland. Despite generally being referred to as flat and lowlands, the Plains’ elevation begins at over a mile above sea level at the foot of the Rockies, before gradually dropping to around 1,500 feet at its eastern edge, often with rolling hills in between. Much of the land in the Midwest and South is used for agricultural purposes – the northern states make up much of the corn belt and are where most oats and soybeans are grown, while wheat and sorghum are grown all over the plains region, and cotton and rice production is more concentrated in the south and southeast. These states are also growing increasingly important for wind energy production, along with the west coast – yet Texas remains the largest energy producer in the U.S. in terms of both renewable and fossil fuel energy.

The Missouri River, the longest river in the U.S., flows from the Rocky Mountains in Montana across the Northern Plains to St. Louis, Missouri, where it then converges with the Mississippi River. The Mississippi itself is the second longest river in the U.S., but its watershed is the country’s largest drainage system. This network of rivers, streams, and other tributaries (known as a drainage basin) stretches across 32 states, and the Mississippi River carries over 40 percent of the country’s drainage into the ocean. Other major rivers that flow from the Rockies into the Mississippi are the Arkansas and Red rivers, while the Ohio River is the largest tributary from the east. The five Great Lakes are found in the northeast, and make up a large part of the Canadian border (although Lake Michigan is located entirely within the U.S.). These are the largest group of freshwater lakes on earth (by surface area) and contain over one fifth of the world’s surface freshwater. The megalopolis around the Great Lakes is the most populous in North America, with over 85 million people on both sides of the border, and extends from Quebec City, Canada as far south as St. Louis.

East

The Great Lakes and Mississippi basin are mostly separated from the eastern seaboard by the Appalachian Mountains. This network of mountain ranges rises in Alabama and Georgia, and extends into Canada, making the northeastern coast more rugged and mountainous than the south. The Appalachians are among the oldest mountain ranges in the world; millions of years ago, its peaks may have reached the same heights as the Rockies, but erosion has caused them to shrink and become rounder over time – nonetheless, the Appalachian’s highest point is still almost 6,700 feet above sea level. While this is one of the most established coal producing regions in the country, it is also renowned for its scenic landscapes - the Appalachian Trail is one of the most well known hiking routes in the country; an outdoor pastime that is growing in popularity each year.

East and South of the Appalachians are generally the lowest regions of the United States. The east coast, the most densely populated region, has a population upwards of 50 million people between Washington D.C. and Boston. Historically, this was the first major area of European settlement, and it remains the most built-up and urbanized region in the country today. Unlike the west, the east and Gulf coasts have many smaller rivers flowing into the sea, and, in combination with the Mississippi watershed, these are responsible for the majority of the country’s wetlands being located in the south and east. These coasts also have some of the longest and most popular beaches in the country, with the Florida peninsula in particular being famous for its unique climate, terrain, and tourist hotspots.