Geographical position.

The United States of America is the world's third largest country with an area of 9.6 million square kilometers, the population — over 300 million people (2007). Most of the country is in the central part of North America. It is bordered by Canada on the north and Mexico on the south, the Atlantic Ocean to the east and the Pacific Ocean to the west.

Due to its geographical position and administrative division the United States is one of the few fragmented countries in the world. Of the fifty states of the country forty-eight states are conterminous, or enclosed within one common boundary. The other two states, Alaska and Hawaii, are located apart from the rest of the country. Alaska is locat­ed in the far northwestern part of North America, bordering western Canada. Hawaii is in the Pacific Ocean to the south and west of mainland North America. The United States occupies a favourable geographical position. The Atlantic Ocean is of great importance for the country's sea communications with Europe, Africa and South America. The sea routes to Asia and Australia pass over the Pacific Ocean. The sea route through the Panama Canal, which connects the two oceans, runs over the Gulf of Mexico and the Caribbean Sea.

The physical geography of the United States is as varied as that of any other coun­try in the world. There are huge forests, large areas of flat, grassy plains, and deserts. An average elevation of about 762 meters masks some great variations. These variations range from a low of 86 meters below sea level in California to a high of over 6, 000 meters above sea level in Alaska.

The people of the United States are descended from many, many different groups of people from around the world. It is a country of immigrants. The first inhabitants came from Asia, crossing the Bering Strait into Alaska during the last Ice Age. Almost 40, 000 years later, Spanish adventurers entered what is now the southwestern United States by way of Mexico. From that time, migrations have continued — Europeans, Africans, Asians, and other people from the Americas entering the country to live and work, adding their cultures to that of the nation.

The United States is spread over a huge area of the Western Hemisphere. For exam­ple, the total distance between the most eastern Florida Key and most western island of Hawaii is 9, 418 kilometers. The conterminous United States stretches some 4, 664 kilo­meters from Maine in the east to California in the west. From the northern border of North Dakota to the southern border of Texas, it is 2, 585 kilometers.

It is little wonder that within a country so large there can be found so many different landscapes.

The country can be divided from the point of view of physical geography into nine regions. These are: (1) the Coastal plains, (2) the Appalachian Highlands, (3) the Interior Plains, (4) the Interior Highlands, (5) the Rocky Mountains, (6) the Intermontane Plateaus and Basins, (7) the Pacific Coastal Ranges, (8) Alaska, and (9) Hawaii.