Location:
North America, bordering both the North Atlantic Ocean and the North Pacific Ocean, between Canada and Mexico

Geographic coordinates:
38 00 N, 97 00 W

Map references:
North America

Area:
total: 9,833,517 sq km
[see also: Area - total country ranks ]
land: 9,147,593 sq km
[see also: Area - land country ranks ]
water: 685,924 sq km
note: includes only the 50 states and District of Columbia, no overseas territories
country comparison to the world (CIA rank, may be based on non-current data): 4

Area - comparative:
about half the size of Russia; about three-tenths the size of Africa; about half the size of South America (or slightly larger than Brazil); slightly larger than China; more than twice the size of the European Union

Land boundaries:
total: 12,048 km
[see also: Land boundaries - total country ranks ]
border countries (2): Canada 8893 km (including 2477 km with Alaska), Mexico 3155 km
note: US Naval Base at Guantanamo Bay, Cuba is leased by the US and is part of Cuba; the base boundary is 28.5 km

Coastline:
19,924 km
[see also: Coastline country ranks ]

Maritime claims:
territorial sea: 12 nm
[see also: Maritime claims - territorial sea country ranks ]
exclusive economic zone: 200 nm
[see also: Maritime claims - exclusive economic zone country ranks ]
contiguous zone: 24 nm
[see also: Maritime claims - contiguous zone country ranks ]
continental shelf: not specified
[see also: Maritime claims - continental shelf country ranks ]

Climate:
mostly temperate, but tropical in Hawaii and Florida, arctic in Alaska, semiarid in the great plains west of the Mississippi River, and arid in the Great Basin of the southwest; low winter temperatures in the northwest are ameliorated occasionally in January and February by warm chinook winds from the eastern slopes of the Rocky Mountains

Terrain:
vast central plain, mountains in west, hills and low mountains in east; rugged mountains and broad river valleys in Alaska; rugged, volcanic topography in Hawaii

Elevation:
mean elevation: 760 m
[see also: Elevation - mean elevation country ranks ]
lowest point: Death Valley (lowest point in North America) -86 m
highest point: Denali 6,190 m (Mount McKinley) (highest point in North America)
note: the peak of Mauna Kea (4,207 m above sea level) on the island of Hawaii rises about 10,200 m above the Pacific Ocean floor; by this measurement, it is the world's tallest mountain - higher than Mount Everest (8,850 m), which is recognized as the tallest mountain above sea level

Natural resources:
coal, copper, lead, molybdenum, phosphates, rare earth elements, uranium, bauxite, gold, iron, mercury, nickel, potash, silver, tungsten, zinc, petroleum, natural gas, timber, arable land, note, the US has the world's largest coal reserves with 491 billion short tons accounting for 27% of the world's total

Land use:
agricultural land: 44.5% (2011 est.)
[see also: Land use - agricultural land country ranks ]
arable land: 16.8% (2011 est.)
[see also: Land use - arable land country ranks ]
permanent crops: 0.3% (2011 est.)
[see also: Land use - permanent crops country ranks ]
permanent pasture: 27.4% (2011 est.)
[see also: Land use - permanent pasture country ranks ]
forest: 33.3% (2011 est.)
[see also: Land use - forest country ranks ]
other: 22.2% (2011 est.)
[see also: Land use country ranks ]

Irrigated land:
264,000 sq km (2012)
[see also: Irrigated land country ranks ]

Population distribution:
large urban clusters are spread throughout the eastern half of the US (particularly the Great Lakes area, northeast, east, and southeast) and the western tier states; mountainous areas, principally the Rocky Mountains and Appalachian chain, deserts in the southwest, the dense boreal forests in the extreme north, and the central prarie states are less densely populated; Alaska's population is concentrated along its southern coast - with particular emphasis on the city of Anchorage - and Hawaii's is centered on the island of Oahu

Natural hazards:
tsunamis; volcanoes; earthquake activity around Pacific Basin; hurricanes along the Atlantic and Gulf of Mexico coasts; tornadoes in the Midwest and Southeast; mud slides in California; forest fires in the west; flooding; permafrost in northern Alaska, a major impediment to development

volcanism: volcanic activity in the Hawaiian Islands, Western Alaska, the Pacific Northwest, and in the Northern Mariana Islands; both Mauna Loa (4,170 m) in Hawaii and Mount Rainier (4,392 m) in Washington have been deemed Decade Volcanoes by the International Association of Volcanology and Chemistry of the Earth's Interior, worthy of study due to their explosive history and close proximity to human populations; Pavlof (2,519 m) is the most active volcano in Alaska's Aleutian Arc and poses a significant threat to air travel since the area constitutes a major flight path between North America and East Asia; St. Helens (2,549 m), famous for the devastating 1980 eruption, remains active today; numerous other historically active volcanoes exist, mostly concentrated in the Aleutian arc and Hawaii; they include: in Alaska: Aniakchak, Augustine, Chiginagak, Fourpeaked, Iliamna, Katmai, Kupreanof, Martin, Novarupta, Redoubt, Spurr, Wrangell, Trident, Ugashik-Peulik, Ukinrek Maars, Veniaminof; in Hawaii: Haleakala, Kilauea, Loihi; in the Northern Mariana Islands: Anatahan; and in the Pacific Northwest: Mount Baker, Mount Hood; see note 2 under "Geography - note"

Environment - current issues:
air pollution; large emitter of carbon dioxide from the burning of fossil fuels; water pollution from runoff of pesticides and fertilizers; limited natural freshwater resources in much of the western part of the country require careful management; deforestation; mining; desertification; species conservation; invasive species (the Hawaiian Islands are particularly vulnerable)

Environment - international agreements:
party to: Air Pollution, Air Pollution-Nitrogen Oxides, Antarctic-Environmental Protocol, Antarctic-Marine Living Resources, Antarctic Seals, Antarctic Treaty, Climate Change, Desertification, Endangered Species, Environmental Modification, Marine Dumping, Marine Life Conservation, Ozone Layer Protection, Ship Pollution, Tropical Timber 83, Tropical Timber 94, Wetlands, Whaling
signed, but not ratified: Air Pollution-Persistent Organic Pollutants, Air Pollution-Volatile Organic Compounds, Biodiversity, Climate Change-Kyoto Protocol, Hazardous Wastes

Geography - note:

note 1: world's third-largest country by size (after Russia and Canada) and by population (after China and India); Denali (Mt. McKinley) is the highest point in North America and Death Valley the lowest point on the continent

note 2: the western coast of the United States and southern coast of Alaska lie along the Ring of Fire, a belt of active volcanoes and earthquake epicenters bordering the Pacific Ocean; up to 90% of the world's earthquakes and some 75% of the world's volcanoes occur within the Ring of Fire

note 3: the Aleutian Islands are a chain of volcanic islands that divide the Bering Sea (north) from the main Pacific Ocean (south); they extend about 1,800 km westward from the Alaskan Peninsula; the archipelago consists of 14 larger islands, 55 smaller islands, and hundreds of islets; there are 41 active volcanoes on the islands, which together form a large northern section of the Ring of Fire

note 4: Mammoth Cave, in west-central Kentucky, is the world's longest known cave system with more than 650 km (405 miles) of surveyed passageways, which is nearly twice as long as the second-longest cave system, the Sac Actun underwater cave in Mexico - the world's longest underwater cave system (see "Geography - note" under Mexico);

note 5: Kazumura Cave on the island of Hawaii is the world's longest and deepest lava tube cave; it has been surveyed at 66 km (41 mi) long and 1,102 m (3,614 ft) deep

note 6: Bracken Cave outside of San Antonio, Texas is the world's largest bat cave; it is the summer home to the largest colony of bats in the world; an estimated 20 million Mexican free-tailed bats roost in the cave from March to October making it the world's largest known concentration of mammals