A strait is a naturally formed, typically navigable waterway that connects two larger bodies of water. Most commonly it is a channel of water that lies between two land masses, some straits are not navigable, for example because they are too shallow, or because of an unnavigable reef or archipelago. The terms channel, pass or passage, can be synonymous and used interchangeably with strait, in Scotland firth or kyle are sometimes used as synonyms for strait. Straits can be important shipping routes, and wars have been fought for control of them, numerous artificial channels, called canals, have been constructed to connect two bodies of water over land, such as the Suez Canal. Although rivers and canals often provide passage between two large lakes or a lake and a sea, and these seem to suit the formal definition of strait, the term strait is typically reserved for much larger, wider features of the marine environment. There are exceptions, with straits being called canals, Pearse Canal, Straits are the converse of isthmuses.
That is, while a strait lies between two masses and connects two larger bodies of water, an isthmus lies between two bodies of water and connects two larger land masses. Some straits have the potential to generate significant tidal power using tidal stream turbines, tides are more predictable than wave power or wind power. The Pentland Firth may be capable of generating 10 GW, cook Strait in New Zealand may be capable of generating 5. There may be no suspension of innocent passage through such straits, list of straits Media related to Straits at Wikimedia Commons
The Pacific Ocean is the largest and deepest of the Earths oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean in the south and is bounded by Asia and Australia in the west, the Mariana Trench in the western North Pacific is the deepest point in the world, reaching a depth of 10,911 metres. Both the center of the Water Hemisphere and the Western Hemisphere are in the Pacific Ocean, the oceans current name was coined by Portuguese explorer Ferdinand Magellan during the Spanish circumnavigation of the world in 1521, as he encountered favourable winds on reaching the ocean. He called it Mar Pacífico, which in both Portuguese and Spanish means peaceful sea, important human migrations occurred in the Pacific in prehistoric times. Long-distance trade developed all along the coast from Mozambique to Japan and therefore knowledge, extended to the Indonesian islands but apparently not Australia. By at least 878 when there was a significant Islamic settlement in Canton much of trade was controlled by Arabs or Muslims.
In 219 BC Xu Fu sailed out into the Pacific searching for the elixir of immortality, from 1404 to 1433 Zheng He led expeditions into the Indian Ocean. The east side of the ocean was discovered by Spanish explorer Vasco Núñez de Balboa in 1513 after his expedition crossed the Isthmus of Panama and he named it Mar del Sur because the ocean was to the south of the coast of the isthmus where he first observed the Pacific. Later, Portuguese explorer Ferdinand Magellan sailed the Pacific East to West on a Castilian expedition of world circumnavigation starting in 1519, Magellan called the ocean Pacífico because, after sailing through the stormy seas off Cape Horn, the expedition found calm waters. The ocean was often called the Sea of Magellan in his honor until the eighteenth century, sailing around and east of the Moluccas, between 1525 and 1527, Portuguese expeditions discovered the Caroline Islands, the Aru Islands, and Papua New Guinea. In 1542–43 the Portuguese reached Japan, in 1564, five Spanish ships consisting of 379 explorers crossed the ocean from Mexico led by Miguel López de Legazpi and sailed to the Philippines and Mariana Islands.
The Manila galleons operated for two and a half centuries linking Manila and Acapulco, in one of the longest trade routes in history, Spanish expeditions discovered Tuvalu, the Marquesas, the Cook Islands, the Solomon Islands, and the Admiralty Islands in the South Pacific. In the 16th and 17th century Spain considered the Pacific Ocean a Mare clausum—a sea closed to other naval powers, as the only known entrance from the Atlantic the Strait of Magellan was at times patrolled by fleets sent to prevent entrance of non-Spanish ships. On the western end of the Pacific Ocean the Dutch threatened the Spanish Philippines, Spain sent expeditions to the Pacific Northwest reaching Vancouver Island in southern Canada, and Alaska. The French explored and settled Polynesia, and the British made three voyages with James Cook to the South Pacific and Australia and the North American Pacific Northwest, one of the earliest voyages of scientific exploration was organized by Spain in the Malaspina Expedition of 1789–1794.
It sailed vast areas of the Pacific, from Cape Horn to Alaska and the Philippines, New Zealand and the South Pacific. Growing imperialism during the 19th century resulted in the occupation of much of Oceania by other European powers, and later, Japan, in Oceania, France got a leading position as imperial power after making Tahiti and New Caledonia protectorates in 1842 and 1853 respectively. After navy visits to Easter Island in 1875 and 1887, Chilean navy officer Policarpo Toro managed to negotiate an incorporation of the island into Chile with native Rapanui in 1888, by occupying Easter Island, Chile joined the imperial nations
The Welland Canal is a ship canal in Ontario, connecting Lake Ontario and Lake Erie. It forms a key section of the St. Lawrence Seaway, traversing the Niagara Peninsula from Port Weller to Port Colborne, it enables ships to ascend and descend the Niagara Escarpment and bypass Niagara Falls. Approximately 40,000,000 tonnes of cargo are carried through the canal annually by about 3,000 ocean and it was a major factor in the growth of the city of Toronto. The Welland Canal eclipsed other, narrower canals in the region, such as the Trent-Severn Waterway and, the southern, Lake Erie terminus of the canal is 99.5 metres higher than the northern terminus on Lake Ontario. The canal includes eight 24. 4-metre-wide ship locks, seven of the locks are 233.5 m long and raise passing ships by between 13 and 15 m each. The southernmost lock, is 349.9 m in length, the Garden City Skyway passes over the canal, restricting the maximum height of the masts of the ships allowed on this canal to 35.5 m. All other highway or railroad crossings of the Welland Canal are either movable bridges or subterranean tunnels, the maximum permissible length of a ship in this canal is 225.5 metres.
It takes ships an average of eleven hours to traverse the entire length of the Welland Canal. The Welland Canal Company was incorporated by the Province of Upper Canada, in 1824, One of the petitioners was William Hamilton Merritt, who was in part looking to provide a regular flow of water for his watermills. The construction began at Allanburg, Ontario, on November 30 and this canal opened for a trial run on November 30,1829. After a short ceremony at Lock One, in Port Dalhousie, the first canal ran from Port Dalhousie, Ontario on Lake Ontario south along Twelve Mile Creek to St. Catharines. From there it took a route up the Niagara Escarpment through Merritton, Ontario to Thorold. Ships went east on the Welland River to Chippawa, at the end of the old portage road. Originally, the section between Allanburg and Port Robinson was planned to be carried in a subterranean tunnel, the sandy soil in this part of Ontario made a tunnel infeasible, and a deep open-cut canal was dug instead. A southern extension from Port Robinson opened in 1833, with the founding of Port Colborne and this extension followed the Welland River south to Welland, and split to run south to Port Colborne on Lake Erie.
A feeder canal ran southwest from Welland to another point on Lake Erie, with the opening of the extension, the canal stretched 44 km between the two lakes, with 40 wooden locks. The minimum lock size was 33.5 by 6.7 m, deterioration of the wood used in the 40 locks and the increasing size of ships led to demand for the Second Welland Canal, which used cut stone locks, within just a few years. The public buyout was completed in 1841, and work began to deepen the canal and to reduce the number of locks to 27, each 45.7 by 8.1 m
An anchialine pool or pond is a landlocked body of water with a subterranean connection to the ocean. Depending on the site, it is possible to access the deeper saline water directly in the anchialine pool or sometimes it may be accessible by cave diving. Water levels in anchialine pools often fluctuate with tidal changes due to the coastal location, the range in water levels fluctuations will be decreased and delayed compared to the range and time observed for the adjacent tide. The primary controls on the damping and lag are the distance from the coast, Anchialine pools are extremely common worldwide especially along neo-tropical coastlines where the geology and aquifer system are relatively young, and there is minimal soil development. Such conditions occur notably where the bedrock is limestone or recently formed volcanic lava, many anchialine pools are found on the coastlines of the island of Hawaii, and on the Yucatán Peninsula, where they are locally called cenotes as well as Christmas Island.
Ecological studies of anchialine pools frequently identify regionally rare and sometimes endemic species living in them, in Hawaii, the pools are home to mostly the ʻōpaeʻula. The Sailors Hat crater created by an explosives test in 1965 is an anchialine pool, brackish water Cenote Anchialine Pool Information United States Geological Survey, National Park Service 2005 Anchialine Caves and Cave Fauna of the World
The Crinan Canal between Crinan and Ardrishaig in Argyll and Bute in the west of Scotland is operated by Scottish Canals. The canal, which opened in 1801, takes its name from the village of Crinan at its western end and it was designed by civil engineer John Rennie and work started in 1794, but was not completed until 1801, two years than planned. The canals construction was beset with problems including finance and poor weather, landowners demanded high prices for their land and navvies were reluctant to leave jobs in more accessible parts of England and Scotland. The canal bank near Lochgilphead failed in 1805 and the course was diverted to avoid the marshy ground. The canal company, headed by the Duke of Argyll, had to help from the government. He suggested improvements to the locks, and some parts of the canal were redesigned including the bridges which were replaced in cast iron in 1816. The government paid for the work but the company lost control. Queen Victoria travelled along the canal to Crinan during a holiday in the Scottish Highlands in 1847 and she was greeted at Ardrishaig and her boat was towed by four horses, two of which were ridden by postilions in royal livery.
At Crinan she boarded the royal yacht Victoria and Albert and her journey made the canal a tourist attraction and gave the canal an added purpose. In 1866 a steam-powered passenger boat Linnet replaced horse-drawn boats for tourists, Linnet remained in service until 1929. Between 1930 and 1932, new sea locks were built at either end, the swing bridge at Ardrishaig was installed at this time. The canal became the responsibility of British Waterways in 1962 and it closed for nine-week period in October 1987 to allow some refurbishment. On 2 July 2012 the British Waterways functions in Scotland were transferred to Scottish Canals, today the canal is a popular route for leisure craft between the Firth of Clyde and the west coast of Scotland, used by nearly 2,000 boats annually. The towpath is part of National Cycle Route 78, which links Campbeltown, Fort William, the Crinan Canal has 15 locks and is crossed by seven bridges, six swing bridges and a retractable bridge. Stone for the 15 locks was brought from Mull, the Isle of Arran, from Ardrishaig, three locks raise the canals four-mile long east reach to 32 feet above sea level.
The 1, 100-yard summit reach, between Cairnbaan and Dunardry, is 64 feet above sea level, the west reach between Dunardry and Crinan is 18 feet above sea level. The canal is 10 ft deep and has no height limit. The retractable bridge at Lock 11 replaced the swing bridge in 1900
Canals and navigations are human-made channels for water conveyance, or to service water transport vehicles. In the vernacular, both are referred to as canals, and in most cases, the works will have a series of dams. These areas are referred to as water levels, often just called levels. In contrast, a canal cuts across a drainage divide atop a ridge, many canals have been built at elevations towering over valleys and others water ways crossing far below. Cities need a lot of water and many canals with sources of water at a higher level can deliver water to a destination where there is a lack of water. The Roman Empires Aqueducts were such water supply canals, a navigation is a series of channels that run roughly parallel to the valley and stream bed of an unimproved river. A navigation always shares the drainage basin of the river, a vessel uses the calm parts of the river itself as well as improvements, traversing the same changes in height. A true canal is a channel that cuts across a drainage divide, most commercially important canals of the first half of the 19th century were a little of each, using rivers in long stretches, and divide crossing canals in others.
This is true for many canals still in use, there are two broad types of canal, Waterways and navigations used for carrying vessels transporting goods and people. These can be subdivided into two kinds, Those connecting existing lakes, other canals or seas and oceans and those connected in a city network, such as the Canal Grande and others of Venice Italy, the gracht of Amsterdam, and the waterways of Bangkok. Aqueducts, water canals that are used for the conveyance and delivery of potable water for human consumption, municipal uses, hydro power canals. Historically canals were of importance to commerce and the development, growth. In 1855 the Lehigh Canal carried over 1.2 million tons of burning anthracite coal, by the 1930s the company which built. By the early 1880s, canals which had little ability to compete with rail transport, were off the map. In the next couple of decades, coal was diminished as the heating fuel of choice by oil. Later, after World War I when motor-trucks came into their own, Canals are built in one of three ways, or a combination of the three, depending on available water and available path, Human made streams A canal can be created where no stream presently exists.
Either the body of the canal is dug or the sides of the canal are created by making dykes or levees by piling dirt, the water for the canal must be provided from an external source, like streams or reservoirs. Where the new waterway must change elevation engineering works like locks, lifts or elevators are constructed to raise, examples include canals that connect valleys over a higher body of land, like Canal du Midi, Canal de Briare and the Panama Canal
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait, to the north lie the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez. The Red Sea is a Global 200 ecoregion, the sea is underlain by the Red Sea Rift which is part of the Great Rift Valley. The Red Sea has an area of roughly 438,000 km2, is about 2250 km long and. It has a depth of 2211 m in the central median trench. However, there are extensive shallow shelves, noted for their marine life, the sea is the habitat of over 1,000 invertebrate species, and 200 soft and hard corals. It is the worlds northernmost tropical sea, the International Hydrographic Organization defines the limits of the Red Sea as follows, On the North. The Southern limits of the Gulfs of Suez and Aqaba, a line joining Husn Murad and Ras Siyyan. Red Sea is a translation of the Greek Erythra Thalassa, Latin Mare Rubrum, Arabic, البحر الأحمر. Al-Baḥr Al-Aḥmar, Somali Badda Cas and Tigrinya Qeyyiḥ bāḥrī, the name of the sea may signify the seasonal blooms of the red-coloured Trichodesmium erythraeum near the waters surface. A theory favored by modern scholars is that the name red is referring to the direction south.
The basis of this theory is that some Asiatic languages used color words to refer to the cardinal directions, herodotus on one occasion uses Red Sea and Southern Sea interchangeably. Historically, it was known to western geographers as Mare Mecca. Some ancient geographers called the Red Sea the Arabian Gulf or Gulf of Arabia. C, in that version, the Yam Suph is translated as Erythra Thalassa. The Red Sea is one of four seas named in English after common color terms — the others being the Black Sea, the White Sea and the Yellow Sea. The direct rendition of the Greek Erythra thalassa in Latin as Mare Erythraeum refers to the part of the Indian Ocean. The earliest known exploration of the Red Sea was conducted by ancient Egyptians, one such expedition took place around 2500 BC, and another around 1500 BC. Both involved long voyages down the Red Sea, scholars argued whether these trips were possible
Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. Europe covers about 10,180,000 square kilometres, or 2% of the Earths surface, Europe is divided into about fifty sovereign states of which the Russian Federation is the largest and most populous, spanning 39% of the continent and comprising 15% of its population. Europe had a population of about 740 million as of 2015. Further from the sea, seasonal differences are more noticeable than close to the coast, Europe, in particular ancient Greece, was the birthplace of Western civilization. The fall of the Western Roman Empire, during the period, marked the end of ancient history. Renaissance humanism, exploration and science led to the modern era, from the Age of Discovery onwards, Europe played a predominant role in global affairs. Between the 16th and 20th centuries, European powers controlled at times the Americas, most of Africa, Oceania.
The Industrial Revolution, which began in Great Britain at the end of the 18th century, gave rise to economic and social change in Western Europe. During the Cold War, Europe was divided along the Iron Curtain between NATO in the west and the Warsaw Pact in the east, until the revolutions of 1989 and fall of the Berlin Wall. In 1955, the Council of Europe was formed following a speech by Sir Winston Churchill and it includes all states except for Belarus and Vatican City. Further European integration by some states led to the formation of the European Union, the EU originated in Western Europe but has been expanding eastward since the fall of the Soviet Union in 1991. The European Anthem is Ode to Joy and states celebrate peace, in classical Greek mythology, Europa is the name of either a Phoenician princess or of a queen of Crete. The name contains the elements εὐρύς, broad and ὤψ eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion and the poetry devoted to it.
For the second part the divine attributes of grey-eyed Athena or ox-eyed Hera. The same naming motive according to cartographic convention appears in Greek Ανατολή, Martin Litchfield West stated that phonologically, the match between Europas name and any form of the Semitic word is very poor. Next to these there is a Proto-Indo-European root *h1regʷos, meaning darkness. Most major world languages use words derived from Eurṓpē or Europa to refer to the continent, in some Turkic languages the originally Persian name Frangistan is used casually in referring to much of Europe, besides official names such as Avrupa or Evropa
The Suez Canal is an artificial sea-level waterway in Egypt, connecting the Mediterranean Sea to the Red Sea through the Isthmus of Suez. It was constructed by the Suez Canal Company between 1859 and 1869, after 10 years of construction, it was officially opened on November 17,1869. It extends from the terminus of Port Said to the southern terminus of Port Tewfik at the city of Suez. Its length is 193.30 km, including its northern and southern access channels, in 2012,17,225 vessels traversed the canal. The original canal was a waterway with passing locations in the Ballah Bypass. It contains no locks system, with seawater flowing freely through it, in general, the canal north of the Bitter Lakes flows north in winter and south in summer. South of the lakes, the current changes with the tide at Suez, the canal is owned and maintained by the Suez Canal Authority of Egypt. Under the Convention of Constantinople, it may be used in time of war as in time of peace, by every vessel of commerce or of war, without distinction of flag.
In August 2014, construction was launched to expand and widen the Ballah Bypass for 35 km to speed the canals transit time, the expansion was planned to double the capacity of the Suez Canal from 49 to 97 ships a day. At a cost of $8.4 billion, this project was funded with interest-bearing investment certificates issued exclusively to Egyptian entities, the New Suez Canal, as the expansion was dubbed, was opened with great fanfare in a ceremony on 6 August 2015. On 24 February 2016, the Suez Canal Authority officially opened the new side channel and this side channel, located at the northern side of the east extension of the Suez Canal, serves the East Terminal for berthing and unberthing vessels from the terminal anytime of day and night. Ancient west–east canals were built to travel from the Nile River to the Red Sea. One smaller canal is believed to have been constructed under the auspices of Senusret II or Ramesses II. Another canal, probably incorporating a portion of the first, was constructed under the reign of Necho II, the legendary Sesostris may have started work on an ancient canal joining the Nile with the Red Sea.
In his Meteorology, Aristotle wrote, One of their kings tried to make a canal to it, so he first, and Darius afterwards, stopped making the canal, lest the sea should mix with the river water and spoil it. Strabo wrote that Sesostris started to build a canal, and Pliny the Elder wrote,165. Later the Persian king Darius had the idea, and yet again Ptolemy II. This proved to be the canal made by the Persian king Darius I
Isthmus of Corinth
The Isthmus of Corinth is the narrow land bridge which connects the Peloponnese peninsula with the rest of the mainland of Greece, near the city of Corinth. The word isthmus comes from the Ancient Greek word for neck, the Isthmus was known in the ancient world as the landmark separating the Peloponnese from mainland Greece. In the first century CE the geographer Strabo noted a stele on the Isthmus of Corinth, to the west of the Isthmus is the Gulf of Corinth, to the east the Saronic Gulf. Since 1893 the Corinth Canal has run through the 6.3 km wide isthmus, two road bridges, two railway bridges and two submersible bridges at both ends of the canal connect the mainland side of the isthmus with the Peloponnese side. Also a military emergency bridge is located at the west end of the canal, the idea for a shortcut to save boats sailing all round the Peloponnese was long considered by the Ancient Greeks. The first attempt to build a canal there was carried out by the tyrant Periander in the 7th century BC and he abandoned the project owing to technical difficulties, and instead constructed a simpler and less costly overland stone ramp, named Diolkos, as a portage road.
Remnants of Diolkos still exist today next to the modern canal, when the Romans took control of Greece, a number of different solutions were tried. Julius Caesar foresaw the advantages of a link for his newly built Colonia Laus Iulia Corinthiensis, by the reign of Tiberius, engineers tried to dig a canal, but were defeated by lack of modern equipment. Instead they built an Ancient Egyptian device, boats were rolled across the isthmus on logs and this was in use by AD32. In AD67, the philhellene Roman emperor Nero ordered 6,000 slaves to dig a canal with spades, historian Flavius Josephus writes that the 6000 slaves were Jewish pirates, taken captive by Vespasian during the Jewish wars. According to Pliny the Elder, the work advanced four stadia, the following year Nero died, and his successor Galba abandoned the project as being too expensive. In the modern era, the idea was first seriously proposed in 1830, soon after Greeces independence from the Ottoman Empire, near the canal runs an ancient stone trackway, the Diolkos, once used for dragging ships overland.
There are major concerns about preservation of this path, Greek campaigners are calling for greater effort by the Greek government to protect this archaeological site. The Hexamilion wall is a Roman defensive wall constructed across the Isthmus of Corinth guarding the land route into the Peloponnese peninsula from mainland Greece
Lake Erie is the fourth-largest lake of the five Great Lakes in North America, and the thirteenth-largest globally if measured in terms of surface area. It is the southernmost and smallest by volume of the Great Lakes, at its deepest point Lake Erie is 210 feet deep. Lake Eries northern shore is bounded by the Canadian province of Ontario, with the U. S. states of Ohio and these jurisdictions divide the surface area of the lake by water boundaries. The lake was named by the Erie people, a Native Americans people who lived along its southern shore and that Iroquoian tribe called it Erige because of its unpredictable and sometimes violently dangerous nature. It is a matter of whether the lake was named after the tribe. Situated below Lake Huron, Eries primary inlet is the Detroit River, Lake Erie has a mean elevation of 571 feet above sea level. It has an area of 9,990 square miles with a length of 241 statute miles. The warm summer of 1999 caused lake temperatures to come close to the 85 °F limit necessary to keep the plants cool, because of its shallowness, and in spite of being the warmest lake in the summer, it is the first to freeze in the winter.
The waves build very quickly, according to other accounts, after being trapped for an hour-and-a-half, Baker was back on dry land and battered but alive. This area is known as the thunderstorm capital of Canada with breathtaking lightning displays. Lake Erie is primarily fed by the Detroit River and drains via the Niagara River, navigation downstream is provided by the Welland Canal, part of the Saint Lawrence Seaway. Other major contributors to Lake Erie include the Grand River, the Huron River, the Maumee River, the Sandusky River, the Buffalo River, the drainage basin covers 30,140 square miles. Point Pelee National Park, the southernmost point of the Canadian mainland, is located on a peninsula extending into the lake. Several islands are found in the end of the lake, these belong to Ohio except for Pelee Island and eight neighboring islands. Major cities along Lake Erie include Buffalo, Pennsylvania, Ohio, Islands tend to be located in the western side of the lake and total 31 in number.
The island-village of Put-in-Bay on South Bass Island attracts young crowds who sometimes wear red hats and are prone to break off cartwheels in the park. Pelee Island is the largest of Eries islands, accessible by ferry from Leamington and Sandusky, songbirds migrate to Pelee in spring, and monarch butterflies stop over during the fall. Lake Erie has a retention time of 2.6 years
The Americas, collectively called America, encompass the totality of the continents of North America and South America. Together they make up most of the land in Earths western hemisphere, along with their associated islands, they cover 8% of Earths total surface area and 28. 4% of its land area. The topography is dominated by the American Cordillera, a chain of mountains that runs the length of the west coast. The flatter eastern side of the Americas is dominated by river basins, such as the Amazon, St. Lawrence River / Great Lakes basin, Mississippi. Humans first settled the Americas from Asia between 42,000 and 17,000 years ago, a second migration of Na-Dene speakers followed from Asia. The subsequent migration of the Inuit into the neoarctic around 3500 BCE completed what is regarded as the settlement by the indigenous peoples of the Americas. The first known European settlement in the Americas was by the Norse explorer Leif Ericson, the colonization never became permanent and was abandoned.
The voyages of Christopher Columbus from 1492 to 1502 resulted in permanent contact with European powers, diseases introduced from Europe and Africa devastated the indigenous peoples, and the European powers colonized the Americas. Mass emigration from Europe, including numbers of indentured servants. Decolonization of the Americas began with the American Revolution in 1776, the population is over 1 billion, with over 65% of them living in one of the three most populous countries. As of the beginning of the 2010s, the most populous urban agglomerations are Mexico City, New York, Sao Paulo, Los Angeles, Buenos Aires and Rio de Janeiro, all of them megacities. The name America was first recorded in 1507 in the Cosmographiae Introductio, apparently written by Matthias Ringmann and it first applied to both North and South America by Gerardus Mercator in 1538. Amerigen means land of Amerigo and derives from Amerigo and gen, America accorded with the feminine names of Asia and Europa. When conceived as a continent, the form is generally the continent of America in the singular.
However, without a context, singular America in English commonly refers to the United States of America. In some countries of the world, America is considered a continent encompassing the North America and South America subcontinents, the first inhabitants migrated into the Americas from Asia. Habitation sites are known in Alaska and the Yukon from at least 20,000 years ago, beyond that, the specifics of the Paleo-Indian migration to and throughout the Americas, including the dates and routes traveled, are subject to ongoing research and discussion. Widespread habitation of the Americas occurred during the glacial maximum