Total area: 9,372,610 km2
land area: 9,166,600 km2; includes only the 50 states and District of Colombia

Comparative area: about four-tenths the size of USSR; about one-third the size of Africa; about one-half the size of South America (or slightly larger than Brazil); slightly smaller than China; about two and one-half times the size of Western Europe

Land boundaries: 12,248 km total
Canada 8,893 km (including 2,477 km with Alaska), Mexico 3,326 km, Cuba (US naval base at Guantanamo) 29 km

Coastline: 19,924 km

Maritime claims: Contiguous zone: 12 nm
Continental shelf: not specified
Exclusive economic zone: 200 nm
Territorial sea: 12 nm

Disputes: maritime boundary disputes with Canada; US Naval Base at Guantanamo is leased from Cuba and only mutual agreement or US abandonment of the area can terminate the lease; Haiti claims Navassa Island; US has made no territorial claim in Antarctica (but has reserved the right to do so) and does not recognize the claims of any other nation; Marshall Islands claims Wake Island

Climate: mostly temperate, but varies from tropical (Hawaii) to arctic (Alaska); arid to semiarid in west with occasional warm, dry chinook wind

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

Natural resources: coal, copper, lead, molybdenum, phosphates, uranium, bauxite, gold, iron, mercury, nickel, potash, silver, tungsten, zinc, crude oil, natural gas, timber

Land use: arable land 20%; permanent crops NEGL%; meadows and pastures 26%; forest and woodland 29%; other 25%; includes irrigated 2%

Environment: pollution control measures improving air and water quality; acid rain; agricultural fertilizer and pesticide pollution; management of sparse natural water resources in west; desertification; tsunamis, volcanoes, and earthquake activity around Pacific Basin; continuous permafrost in northern Alaska is a major impediment to development

Note: world's fourth-largest country (after USSR, Canada, and China)

NOTE: The information regarding United States on this page is re-published from the 1991 World Fact Book of the United States Central Intelligence Agency. No claims are made regarding the accuracy of United States Geography 1991 information contained here. All suggestions for corrections of any errors about United States Geography 1991 should be addressed to the CIA.