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Africa is a continent comprising 63 political territories, representing the largest of the great southward projections from the main mass of Earth's surface. Within its regular outline, it comprises an area of , including adjacent islands. Its highest mountain is Mount Kilamanjaro, its largest lake is Lake Victoria and its longest river is the Nile. Separated from Europe by the Mediterranean Sea and from much of Asia by the Red Sea, Africa is joined to Asia at its northeast extremity by the Isthmus of Suez (which is transected by the Suez Canal), wide. For geopolitical purposes, the Sinai Peninsula of Egypt – east of the Suez Canal – is often considered part of Africa. From the most northerly point, Ras ben Sakka in Tunisia, in 37°21′ N, to the most southerly point, Cape Agulhas in South Africa, 34°51′15″ S, is a distance approximately of ; from Cap-Vert, 17°31′13″W, the westernmost point, to Ras Hafun in Somalia, 51°27′52″ E, the most easterly projection, is a distance (also approximately) of . The length of coastline is and the absence of deep indentations of the shore is shown by the fact that Europe, which covers only , has a coastline of . The main structural lines of the continent show both the east-to-west direction characteristic, at least in the eastern hemisphere, of the more northern parts of the world, and the north-to-south direction seen in the southern peninsulas. Africa is thus mainly composed of two segments at right angles, the northern running from east to west, and the southern from north to south. ==Main features== The average elevation of the continent approximates closely to above sea level, roughly near to the mean elevation of both North and South America, but considerably less than that of Asia, . In contrast with other continents, it is marked by the comparatively small area of either very high or very low ground, lands under occupying an unusually small part of the surface; while not only are the highest elevations inferior to those of Asia or South America, but the area of land over is also quite insignificant, being represented almost entirely by individual peaks and mountain ranges. Moderately elevated tablelands are thus the characteristic feature of the continent, though the surface of these is broken by higher peaks and ridges. (So prevalent are these isolated peaks and ridges that a specialised term () has been adopted in Germany to describe this kind of country, thought to be in great part the result of wind action.) As a general rule, the higher tablelands lie to the east and south, while a progressive diminution in altitude towards the west and north is observable. Apart from the lowlands and the Atlas mountain range, the continent may be divided into two regions of higher and lower plateaus, the dividing line (somewhat concave to the north-west) running from the middle of the Red Sea to about 6 deg. S. on the west coast... Africa can be divided into a number of geographic zones: *The coastal plains — often fringed seawards by mangrove swamps — never stretching far from the coast, apart from the lower courses of streams. Recent alluvial flats are found chiefly in the delta of the more important rivers. Elsewhere, the coastal lowlands merely form the lowest steps of the system of terraces that constitutes the ascent to the inner plateaus. *The Atlas range — orthographically distinct from the rest of the continent, being unconnected with and separated from the south by a depressed and desert area (the Sahara). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Geography of Africa」の詳細全文を読む スポンサード リンク
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