Exploration is a quest for the unknown. Earliest records show evidence of humanity's unquenchable curiosity about unknown places and peoples, and in more than 3,000 years of recorded history, men and women have explored most of the Earth's surface by land and sea. This article will survey that exploration. It will not include deep-sea, underground, and space explorations, which are more recent and continue today. The concept of world exploration is used in a European context: from the eastern Mediterranean in ancient times; from western Europe in the 15th and 16th centuries; and from Europe or areas of European culture in the 18th, 19th, and 20th centuries. Explorers have been motivated by curiosity, by a desire to find riches, and by the need to find a place for surplus populations. Some have explored by accident, others as a result of military campaigns, but most have explored by design. Colonization, often brought about by exploration, has frequently resulted in further exploration, and in modern times, the quest for scientific knowledge has sometimes spurred explorations. ANCIENT AND MEDIEVAL EXPLORATIONS The early Egyptians, whose civilization centered on the Nile River, were aware of and used the Mediterranean Sea. The Assyrians, whose civilization was based on the Tigris and Euphrates rivers, followed those rivers to the Persian Gulf; they also went overland to the Mediterranean. The Minoans on the island of Crete sent ships at least as far as Sicily before 1500 BC. The Phoenicians, from their base in what is now Lebanon, ranged throughout the Mediterranean, establishing trading posts at Carthage and Gades (now Cadiz, Spain). They also are thought to have made a 3-year voyage around Africa, from east to west, about 600 BC. The Carthaginians certainly sailed beyond Gibraltar to establish trading posts on the West African coast. By the 8th century BC the Greeks had moved into the Black Sea and also sailed widely on the Mediterranean, establishing colonies in Libya, on Sicily, and at Massilia (Marseille, France). \TAlexander the Great\t of Macedonia marched to the east to defeat the Persians and then went farther into Asia, finally reaching India in 326 BC. Pytheas, a Greek from Massilia, ventured westward beyond the Mediterranean about 325 BC. He visited the British Isles and tin mines there and went farther north to a place he called Thule, probably Norway or Baltic territory. Roman civilization, centered in Italy, absorbed Greece and its colonies and Egypt and, in 146 BC, destroyed Carthage. Carthage's colonies and trading posts were taken, and the Mediterranean became a Roman sea--the Mare Nostrum. The Romans were not active explorers, but they vastly expanded their empire and followed a trade route down the Red Sea and to India. This route, later extended to China, made possible the importation of various oriental luxuries for wealthy Romans. The fall of the Roman Empire brought a drastic decline in European trade with Asia by both sea and land. A major revival of interest in Asia did not come until the period of the Crusades, after AD 1096, when the Crusaders developed a liking for oriental goods. The Muslim Arabs, against whom the crusaders were fighting, had sailed to India and China. The rise of the Mongols in Central Asia made possible relatively safe travel for Europeans. Pope Innocent IV sent Giovanni da Pian del \TCarpini\t eastward by land. Between 1245 and 1247 he reached Karakorum in Mongolia and returned with a travel account that aroused much interest. The Polo family's travels in the 13th century did much to revive European interest in distant points. Niccolo and Matteo Polo went from Venice to Peking and back between 1260 and 1269. They returned to Asia in 1271, taking Niccolo's young son Marco, by way of the overland \TSilk Road\t. They remained for 24 years, while Marco held responsible posts under Kublai Khan. The Polos returned to Europe, mostly by sea, in 1295, and Marco \Tpolo\t's account of his travels became widely known. \TIbn Battuta\t, a Muslim judge from Tangier who traveled widely in the Islamic world between 1325 and 1354, also reported on his travels. Centuries earlier the \TVikings\t had sailed from Scandinavia eastward through the Baltic to Russia and southward to what are now the British Isles, France, and Sicily. They also went westward across the North Atlantic, reaching Iceland about 870, where they found some Irish monks. From Iceland they moved farther west to Greenland in the 980s, after which voyages were made to \TVinland\t and other sites in North America. Efforts to settle Vinland failed, and eventually the Greenland colony died out. These Norse explorations seem to have had little effect on later explorations. AGE OF DISCOVERY The great Age of Discovery is dated from 1415, when western Europeans, beginning with the Portuguese, began to venture into the Atlantic Ocean, down the African coast and to the west. Prince \THenry the Navigator\t, a younger son of King John I of Portugal, devoted his life to the cause of exploration: to opening a sea route for trade with India and to locating \TPrester John\t, the legendary Christian ruler, in Africa. Although Henry never left Portugal, he sent ships down the African coast and worked to improve the ships, their instruments, and maps. By his death in 1460, the Portuguese had rounded the bulge of West Africa and reached the Guinea coast. The Portuguese crown continued to support exploration. In 1488, Bartolomeu \TDias\t finally rounded the southern tip of Africa and reached the East African coast. Vasco da \TGama\t left Portugal in 1497 on an expedition around Africa and across the Indian Ocean to Calicut in India; he opened a sea route, making possible further Portuguese advances into Asia and a Portuguese overseas empire. Between the voyages of Dias and da Gama, a Genoese who had been in Portugal went to Spain and in 1492 persuaded \TIsabella I\t of Castile to fund a voyage to reach Asia by sailing west. Christopher \TColumbus\t had underestimated the distance; he thought it was about 4,800 km (3,000 mi). He sailed on Aug. 3, 1492, from Palos and landed on Oct. 12, 1492, in the Bahamas. From San Salvador (Watling Island) he sailed to and discovered Cuba and Hispaniola, before returning to Spain. In succeeding years, still searching for the Asian mainland, Columbus made three more voyages and discovered many of the Caribbean islands, the mainland of South America, and Central America. Other explorers soon sailed westward. Amerigo \TVespucci\t, of Florence, made two or more voyages, reached South America, and had his name given to the New World by a German mapmaker named Martin Waldseemuller. The second Portuguese fleet to India, led by Pedro Alvares \TCabral\t, took too wide a tack in the South Atlantic and, blown even farther west by storms, reached Brazil in 1500. A Portuguese, Ferdinand \TMagellan\t, sailing under the Spanish flag, sought to prove the Spice Islands were on the Spanish side of the line of demarcation between Spanish and Portuguese spheres of interest established (1494) by the Treaty of \TTordesillas\t. He sailed west in 1519, found the Strait of Magellan near the tip of America, crossed the Pacific, and was killed in the Philippines. One of his captains, Juan Sebastian del \TCano\t, brought his ship, the Victoria, back to Spain, completing in 1522 the first world circumnavigation. Other early explorers of the Americas were John \TCabot\t, a Genoese who sailed under commission from Henry VII of England, reaching Newfoundland in 1497. His son Sebastian \TCabot\t also served Henry VII, spent many years in Spanish service, and then returned to England to supervise exploration for the Northeast Passage. A Florentine, Giovanni da \TVerrazano\t, sailed under French commission. He reached the Carolina coast in 1525 and, moving northward, sighted New York harbor and then sailed on to Maine. Jacques \TCartier\t, a Frenchman who served his own country, reached the lower St. Lawrence River in 1534, and on a second voyage in 1535 got past Quebec's site and as far inland as what is now Montreal. A third voyage helped to pave the way for Samuel de Champlain's expeditions. LATER MARITIME EXPLORATIONS It was the search for a \TNorthwest Passage\t that brought Cartier into the St. Lawrence River in 1534. Subsequent early attempts included the voyages of Sir Martin \TFrobisher\t and John \TDavis\t, exploring west of Greenland in the 1570s and 1580s, that of Henry \THudson\t reaching Hudson Bay in 1610, and that of William \TBaffin\t, who sailed into Baffin Bay in 1616. Not until the 19th century was another major effort mounted to find the Northwest Passage. The search for a \TNortheast Passage\t was begun in 1553 by the English Muscovy Company. Richard \Tchancellor\t reached the White Sea and then went overland to Moscow. A Dutchman, Willem \TBarents\t, discovered Spitsbergen in the 1590s and got to the Kara Sea. In 1607 and 1609, Henry Hudson was stopped by ice. Russians worked from the Pacific side. Semyon I. Dezhnev (c.1605-1673) went in 1648 from the Arctic coast of Siberia through the Bering Strait to the Pacific, while Vitus \TBering\t, a Dane sailing under the Russian flag, explored the region in the 1720s. From \TPtolemy\t's time (AD 150) a great southern continent was thought to exist. The idea was revived in the mid-16th century. Early Spanish and Portuguese voyagers to the South Pacific could not find it. Sir Francis \TDrake\t, on his circumnavigation (1577-80), reached some islands south of Cape Horn, but the Dutch made the major discoveries. Willem Janszoon went to New Guinea and found Australia in 1606. Abel \TTasman\t discovered Tasmania and New Zealand in 1642 and sailed around Australia on the south, proving it an island. In 1769-70 the British Captain James \TCook\t circumnavigated both islands of New Zealand and surveyed and mapped approximately 3,200 km (2,000 mi) of previously unknown east Australian coast. None of these voyages, however, located the great southern continent. The Antarctic mainland was not found until 1820, when Nathaniel B. \TPalmer\t and Edward \TBransfield\t made separate sightings. By the time of Captain Cook's voyages, the value of scientists accompanying exploring expeditions was recognized. Cook's pioneering work in this respect, aided by the British government and the Royal Society, was followed in the 1830s by the voyage (1831-36) of the H. M. S. Beagle, on which Charles \TDarwin\t traveled as the official naturalist. Between 1838 and 1842 a U.S. exploring expedition led by Lieutenant Charles \TWilkes\t, and accompanied by a team of scientists, drew charts of the South Pacific that were used for more than a century. The French had been active in scientific exploration in the 18th century, when Louis Antoine de \TBougainville\t, an officer and scientist, completed the first French-sponsored circumnavigation between 1766 and 1769. Bougainville's explorations in the South Pacific were particularly noteworthy. LAND EXPLORATIONS Exploration over land was more complicated than sailing the seas. Natural obstacles had to be overcome, and expeditions could be mounted only after reaching newly discovered regions by sea. The Spanish, who lacked the great Portuguese seagoing tradition, were more adept on land, largely because of military expertise. The Americas Spanish settlements and colonies in the Americas were begun in the time of Columbus. In 1513 survivors of several Spanish efforts to settle in the Panama region were led across the isthmus to the Pacific Ocean by Vasco Nunez de \TBalboa\t. This was the first crossing of the American continent, and it set the scene for Magellan's voyage and Francisco Pizarro's conquest of Peru. Juan \TPonce de Leon\t traveled twice (1513, 1521) from Puerto Rico to Florida, where he was mortally wounded. However, it was Hernan \Tcortes\t's conquest (1519-21) of Mexico that opened much of North America to Spain. In 1540, Francisco de \TCoronado\t was sent north from Mexico to find the fabled Seven Golden Cities of \TCibola\t. After discovering the Grand Canyon, he got as far as Kansas, but without finding treasure. The following year, Hernando \Tde Soto\t, who had crossed from the Tampa, Fla., area, reached the Mississippi River near Memphis, Tenn. He went on into the Ozarks but returned and died on the Mississippi. Far to the north, French claims to Canada were secured by land explorers' activities. The first governor of New France was Samuel de \TChamplain\t. His explorations took him (1615) as far west as Lake Huron, from which he returned by way of Lake Ontario. His lieutenant Jean \TNicolet\t reached Lake Michigan in 1634. The French also sent explorers to trace the Mississippi: Louis \TJolliet\t and Jacques \TMarquette\t in 1672 and the Sieur de \TLa Salle\t in 1681. Land exploration of the far western parts of North America included efforts (1731-49) by the Sieur de \TLa Verendrye\t and his sons, who went as far west as the Dakotas. After Canada became a British territory, Alexander \TMackenzie\t was sent west in 1789 and 1793. He mapped the Mackenzie River to the Arctic Ocean and then crossed the Rockies and reached the Pacific. In the United States, President Thomas Jefferson sent two army officers, Meriwether \TLewis\t and William \TClark\t, to explore the territory of the \TLouisiana Purchase\t. Between 1804 and 1806 the \TLewis and Clark Expedition\t went up the Missouri River, crossed the Rockies, and descended the Columbia River to the Pacific. In the succeeding decades many other American explorers--among them Zebulon \Tpike\t, Stephen \TLong\t, Jedediah \TSmith\t, and John \TFremont\t--explored the West, establishing routes across the interior to the Pacific. Exploration of South America began with Francisco \TPizarro\t's expedition by sea from Panama to Ecuador and then by land to Peru, where the Inca empire was conquered (1531-33). It was from Peru that Diego de \TAlmagro\t in 1535 and Pedro de \TValdivia\t in 1540 began the conquest of Chile. Another expedition of the same period, led by Francisco de \TOrellana\t, went north from Peru, crossed the Andes, and followed the Amazon River to the Atlantic. Many other Spaniards and Portuguese explored the interior of South America during the 16th century. The main features became known, but exploration and discovery continued into the 20th century. Major advances were made by the German geographer Alexander von \THumboldt\t in 1799-1803. Africa The exploration of the interior of Africa was also a slow process. Between 1768 and 1773, James \TBruce\t, a Scot, had gone through Abyssinia (Ethiopia) and located the source of the Blue Nile. Another Scot, Mungo \TPark\t, explored part of the Niger River in 1795-96 and again in 1805, but the river's course was not finally determined until John and Richard Lander sailed down it in 1830. The best-known African explorer of the 19th century was David \TLivingstone\t, a Scottish medical missionary who worked chiefly in the Zambesi region. Livingstone, who lost contact with the outside world for a time, was found in 1871 by Henry M. \TStanley\t, a journalist writing for New York and London newspapers. In an expedition in 1874-77, Stanley sought to continue Livingstone's explorations and followed the course of the Congo River to the sea. The Royal Geographic Society, founded in 1830, supported the search conducted by British explorers for the source of the White Nile. The first major expedition was that of Richard \TBurton\t and John H. \TSpeke\t in 1857-59. Together they discovered Lake Tanganyika; then Speke alone discovered Lake Victoria and claimed it as the source of the White Nile. Burton disagreed. In 1862, Speke and James Grant found where Lake Victoria emptied into a river. That this was the Nile was confirmed by Samuel W. \TBaker\t, who came up the river from the Sudan in 1864. Asia In the mid-19th century attempts were made to increase knowledge of Central Asia. Russians took a lead in this endeavor. Aleksandr Middendorf (1815-94) worked in Siberia in the 1840s. Nikolai M. Przhevalski (1839-88) crossed the Gobi Desert, explored Mongolia, reached Tibet, and explored in the Kuen Lun in the 1870s and 1880s; he also discovered the wild camel and the Mongolian wild horse, now called Przhevalski's horse. In the 20th century, Sir Aurel \TStein\t explored in Central Asia, and Roy Chapman \TAndrews\t led an expedition to Mongolia during which prehistoric reptile eggs were discovered. Arabia was another area relatively unknown to Europeans. Portuguese ships had touched the South Arabian coast, and an English adventurer, Henry Middleton, reached Mocha on the Red Sea in 1610. In 1761, King Frederick V of Denmark sponsored a scientific expedition, led by Carsten Niehbur (1733-1815), that traveled widely in Arabia; Niehbur alone survived. Other Europeans who traversed interior Arabia in the 19th century included Richard Burton. Australia English settlement in Australia began soon after Captain Cook's voyage, but exploration of the interior came somewhat later. Charles \TSturt\t explored the river systems of southeastern Australia in 1828-30, and Thomas Mitchell continued the same type of work between 1831 and 1836. Ludwig Leichhardt (1813-c.1848) overcame terrible hardships to cross tropical northern Australia in 1844-45, but he disappeared on a cross-Australian expedition in 1848. Robert O'Hara \TBurke\t and W. J. Wills, who used camels, almost succeeded in crossing Australia from south to north in 1860; John McDouall \TStuart\t finally made the crossing on his third try (1861-62) from Adelaide to the site of Port Darwin. More recently, automobiles and airplanes have been used to explore the remote interior regions of Australia. POLAR EXPEDITIONS Polar exploration had its beginnings in the 16th-century quest for a northern passage to Asia. Richard Chancellor, Willem Barents, Henry Hudson, and others searched for a Northeast Passage but were blocked by ice. Martin Frobisher, John Davis, Henry Hudson, and others searched for the Northwest Passage. Sir Francis Drake and, later, Captain Cook and Captain George \TVancouver\t searched for the Northwest Passage from the Pacific side. In the 19th century intensive search for the northern passages was resumed. The disappearance (1845) of Sir John \TFranklin\t in the Arctic focused attention on the Northwest Passage, which was finally traversed by Roald \TAmundsen\t in 1903-06. Meanwhile, the Northeast Passage was sailed by Adolf \TNordenskjold\t from east to west in 1878-79. The quest for the North Pole also became serious in the 19th century. Sir William E. \TParry\t tried to reach it by sledge in 1827. Between 1893 and 1896, Fridtjof \TNansen\t froze his ship, the Fram, into the sea ice in the hope that currents would carry it to the Pole. He and Fredrik Hjalmar Johansen left the ship and tried for the Pole on foot. They were rescued ultimately from Franz Josef Land. Robert E. \TPeary\t and his associate Matthew A. Henson are generally credited with reaching the North Pole by dogsled on Apr. 6, 1909. They had conducted a series of polar expeditions lasting 11 years. Although much of the Arctic region still remains unknown, and explorations continue, access to the North Pole has become relatively easy. Richard E. \TByrd\t flew to the North Pole from Spitsbergen in 1926. In 1958 the U.S.S. Nautilus, a nuclear-powered submarine, reached the Pole under the ice; the U.S.S. Skate repeated the trip and, on Mar. 17, 1959, surfaced through the ice at the North Pole. Captain James Cook was the pioneer of Antarctic exploration. His work was followed by naval exploring expeditions from many nations as well as by sealing voyages. On an expedition in 1819-21 the Russian Admiral Fabian von \TBellingshausen\t circumnavigated the Antarctic continent. Charles Wilkes in 1838-42 and Sir James \TRoss\t in 1839-43 made major sightings. Although an American whaling captain, John \TDavis\t, landed on the continent in 1821, a second landing, by Norwegians, did not occur until 1895. Many expeditions followed. Ernest \TShackleton\t failed to reach the South Pole in 1909 and failed also in an attempt to cross the Antarctic continent in 1914-16. Another Englishman, Captain Robert F. \TScott\t, followed Shackleton's route to the Pole, reaching it on Jan. 16, 1912. However, he found that the Norwegian explorer Roald Amundsen had arrived there before him, on Dec. 14, 1911; Scott's entire group perished on the return journey. Air travel has made Antarctica more accessible; explorations there have continued. In 1989-90, a multinational team led by Will Steger became the first to cross the continent by dogsled. CONCLUSION Explorers now seem to have reached most parts of the Earth's surface. The availability of increasingly sophisticated scientific techniques, however, including photographs taken from space satellites, undoubtedly will continue to show that areas of the Earth have not yet been explored, or fully explored. The quest for knowledge, of which exploration is a part, continues. \TBruce\t B. SOLNICK Bibliography: Berton, P., The Arctic Grail (1988); Day, Alan E., Discovery and Exploration: The Old World (1980) and Search for the Northwest Passage (1986); Cummings, W. P., et al., The Exploration of North America, 1630-1776 (1974); Day, Alan, Discovery and Exploration: The Old World (1980); Delpar, Helen, ed., The Discoverers: An Encyclopedia of Explorers and Exploration (1980); Goetzmann, William H., New Lands, new Men (1985); Hale, R. L., Renaissance Explorers (1972); Lewis, Richard S., From Vinland to Mars: A Thousand Years of Exploration (1976); Mackay, David, In the Wake of Cook: Exploration, Science and Empire 1780-1801 (1985); Morison, Samuel Eliot, The European Discovery of America, 2 vols. (1971-74); Newby, Eric, The Rand-McNally World Atlas of Exploration (1975); Parry, John H., The Age of Reconnaissance (1963; repr. 1982); Perkins, John, To the Ends of the Earth: Four Expeditions to the Arctic, the Congo, the Gobi, and Siberia (1981); Reid, Alan, Discovery and Exploration: A Concise History (1982); Scammell, Geoffrey V., The World Encompassed: The First European Maritime Empires, c. 800-1650 (1981); Steffansson, Vilhjalmur, ed., Great Adventures and Explorations (1949; repr. 1985); Sykes, Sir Percy, A History of Exploration from the Earliest Times to the Present Day (1949; repr. 1976); Weber, Andrew M., Profiles in Exploration (1988); Wilson, Derek, The Circumnavigators (1989). See also: \TAntarctica\t; \TArctic\t; \Toceanography\t; \Tspace exploration\t.