Alaska in the context of "Sitka, Alaska"

The Americas, sometimes collectively called America, are a landmass comprising the totality of North America and South America. When viewed as a single continent, the Americas are the 2nd largest continent by area after Asia and the 3rd largest continent by population. The Americas make up most of the land in Earth's Western Hemisphere and constitute the New World.

Along with their associated islands, the Americas cover 8% of Earth's total surface area and 28.4% of its land area. The topography is dominated by the American Cordillera, a long chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by large river basins, such as the Amazon, St. Lawrence River–Great Lakes, Mississippi, and La Plata basins. Since the Americas extend 14,000 km (8,700 mi) from north to south, the climate and ecology vary widely, from the arctic tundra of Northern Canada, Greenland, and Alaska, to the tropical rainforests in Central America and South America.

A floodplain or flood plain or bottomlands is an area of land adjacent to a river. Floodplains stretch from the banks of a river channel to the base of the enclosing valley, and experience flooding during periods of high discharge. The soils usually consist of clays, silts, sands, and gravels deposited during floods.

Because of regular flooding, floodplains frequently have high soil fertility since nutrients are deposited with the flood waters. This can encourage farming; some important agricultural regions, such as the Nile and Mississippi river basins, heavily exploit floodplains. Agricultural and urban regions have developed near or on floodplains to take advantage of the rich soil and freshwater. However, the risk of inundation has led to increasing efforts to control flooding.

The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States also asserts sovereignty over five major island territories and various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's third-largest land area and third-largest population, exceeding 340 million.

Paleo-Indians first migrated from North Asia to North America over 12,000 years ago, and formed various civilizations. Spanish colonization established Spanish Florida in 1513, the first European colony in what is now the continental United States. British colonization followed with the 1607 settlement of Virginia, the first of the Thirteen Colonies. Enslavement of Africans was practiced in all colonies by 1770 and supplied most of the labor for the Southern Colonies' plantation economy. Clashes with the British Crown over taxation and lack of parliamentary representation sparked the American Revolution, leading to the Declaration of Independence on July 4, 1776. Victory in the 1775–1783 Revolutionary War brought international recognition of U.S. sovereignty and fueled westward expansion, dispossessing native inhabitants. As more states were admitted, a North–South division over slavery led the Confederate States of America to attempt secession and fight the Union in the 1861–1865 American Civil War. With the United States' victory and reunification, slavery was abolished nationally. By 1900, the country had established itself as a great power, a status solidified after its involvement in World War I. Following Japan's attack on Pearl Harbor in 1941, the U.S. entered World War II. Its aftermath left the U.S. and the Soviet Union as rival superpowers, competing for ideological dominance and international influence during the Cold War. The Soviet Union's collapse in 1991 ended the Cold War, leaving the U.S. as the world's sole superpower.

Northern America is the northernmost subregion of North America, as well as the northernmost region in the Americas. The boundaries may be drawn significantly differently depending on the source of the definition. In one definition, it lies directly north of Middle America. Northern America's land frontier with the rest of North America then coincides with the Mexico–United States border. Geopolitically, according to the United Nations' scheme of geographical regions and subregions, Northern America consists of Bermuda, Canada, Greenland, Saint Pierre and Miquelon and the United States (the contiguous United States and Alaska only, excluding Hawaii, Navassa Island, Puerto Rico, the United States Virgin Islands, and other minor U.S. Pacific territories).

Northern Canada (French: le Nord du Canada), colloquially the North or the Territories, is the vast northernmost region of Canada, variously defined by geography and politics. Politically, the term refers to the three territories of Canada: Yukon, Northwest Territories and Nunavut. This area covers about 48 per cent of Canada's total land area, but has less than 0.5 per cent of Canada's population.

The terms "northern Canada" or "the North" may be used in contrast with the far north, which may refer to the Canadian Arctic, the portion of Canada that lies north of the Arctic Circle, east of Alaska and west of Greenland. That said, in many other uses the two areas are treated as a single unit.

In the United States, a county or county equivalent is an administrative subdivision of a state or territory, typically with defined geographic boundaries and some level of governmental authority. The term "county" is used in 48 states, while Louisiana and Alaska have functionally equivalent subdivisions called parishes and boroughs, respectively. Counties and other local governments exist as a matter of U.S. state law, so the specific governmental powers of counties may vary widely between the states, with many providing some level of services to civil townships, municipalities, and unincorporated areas. Certain municipalities are in multiple counties. Some municipalities have been consolidated with their county government to form consolidated city-counties or have been legally separated from counties altogether to form independent cities. Conversely, counties in Connecticut and Rhode Island, eight of Massachusetts's 14 counties, and Alaska's Unorganized Borough have no government power, existing only as geographic distinctions.

The United States Census Bureau uses the term "county equivalent" to describe places that are comparable to counties, but called by different names. Louisiana parishes, the organized boroughs of Alaska, independent cities, and the District of Columbia are equivalent to counties for administrative purposes. Alaska's Unorganized Borough is further divided into 11 census areas that are statistically equivalent to counties. In 2024, the U.S. Census Bureau began to also recognize Connecticut's councils of governments, which took over some of the regional powers from the state's former county governments, as county equivalents.

A borough in some U.S. states is a unit of local government or other administrative division below the level of the state. The term is currently used in six states:

• A type of municipality: Connecticut, New Jersey and Pennsylvania (also formerly Michigan and Minnesota)
• A subdivision of a consolidated city, corresponding to another present or previous political subdivision: New York and Virginia
• In Alaska only, a borough is a county-equivalent.