Mainland U.S.
The contiguous United States or officially the conterminous United States consists of the 48 adjoining U.S. states plus Washington, D.C. on the continent of North America. The terms exclude the non-contiguous states of Alaska and Hawaii, and all off-shore insular areas, These differ from the related term continental United States which includes Alaska (also on the North American continent but separated from the 48 states by British Columbia, Canada) but excludes Hawaii and insular territories.
The greatest distance (on a great circle route) entirely within the 48 contiguous states is 2,802 miles (4,509 km, between Florida and the State of Washington); the greatest north-south line is 1,650 miles (2,660 km).
Together, the 48 contiguous states and Washington, D.C. occupy a combined area of 3,119,884.69 square miles (8,080,464.3 km2), which is 1.58% of the total surface area of Earth. Of this area, 2,959,064.44 square miles (7,663,941.7 km2) is contiguous land, composing 83.65% of total U.S. land area, similar to the area of Australia. Officially, 160,820.25 square miles (416,522.5 km2) of the contiguous United States is water area, composing 62.66% of the nation's total water area.
The contiguous United States would be placed 5th in the list of sovereign states and dependencies by area; the total area of the country, including Alaska and Hawaii, ranks fourth. Brazil is the only country that is larger in total area than the contiguous United States, but smaller than the entire United States, while Russia, Canada and China are the only three countries larger than both. The 2010 census population of this area was 306,675,006, comprising 99.33% of the nation's population, and a density of 103.639 inhabitants/sq mi (40.015/km2), compared to 87.264/sq mi (33.692/km2) for the nation as a whole.
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