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101-564: Cape Town lies at the south-western corner of the continent of Africa. It is bounded to the south and west by the Atlantic Ocean, and to the north and east by various other municipalities in the Western Cape province of South Africa. The Cape Peninsula is a rocky and mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the continent. At its tip

202-459: A prison where people were isolated, banished, and exiled for nearly 400 years. It was also used as a leper colony, a post office, a grazing ground, a mental hospital, and an outpost. The Cape Peninsula is a rocky and mountainous peninsula that juts out into the Atlantic Ocean at the south-western extremity of the continent. At its tip is Cape Point and the Cape of Good Hope . The peninsula forms

303-510: A severe water shortage from 2015 to 2018. According to Oxfam , "in the face of an imminent water shortage, the city of Cape Town in South Africa successfully reduced its water use by more than half in three years, cutting it from 1.2bn litres per day in February 2015 to 516m litres per day in 2018." In 2021 Cape Town also experienced a violent turf war between rival taxi firms which led to

404-603: A few other towns. Industry and commerce is largely in service of the area. After the Cape Peninsula, Helderberg is the next most mountainous part of Greater Cape Town, bordered to the north and east by the highest peaks in the region along the watershed of the Helderberg and Hottentots Holland Mountains, which are part of the Cape Fold Belt with Cape Supergroup strata on a basement of Tygerberg Formation rocks intruded by part of

505-671: A flood of immigration into South Africa. In 1895 the city's first public power station, the Graaff Electric Lighting Works , was opened. Conflicts between the Boer republics in the interior and the British colonial government resulted in the Second Boer War of 1899–1902. Britain's victory in this war led to the formation of a united South Africa. From 1891 to 1901, the city's population more than doubled from 67,000 to 171,000. As

606-532: A major gap at the Fish Hoek–Noordhoek valley. In the south much of the area is a low sandstone plateau with sand dunes. Maximum altitude is 1113 m on Table Mountain. The Cape Flats (Afrikaans: Kaapse Vlakte) is a flat, low-lying, sandy area, area to the east the Cape Peninsula, and west of the Helderberg much of which was wetland and dunes within recent history. To the north are the Tygerberg Hills and

707-448: A number of satellite towns, suburbs and rural areas such as Atlantis , Bellville , Blouberg , Brackenfell , Durbanville , Goodwood , Gordon's Bay , Hout Bay , Khayelitsha , Kraaifontein , Kuilsrivier , Macassar , Melkbosstrand , Milnerton , Muizenberg , Noordhoek , Parow , Philadelphia , Simon's Town , Somerset West , and Strand among others. The Cape Peninsula is 52 km (30 mi) long from Mouille Point in

808-452: A region is the product of its long weathering history; leaching and dispersion are dominant during the initial phase of weathering under humid conditions. Saprolites form in high rainfall regions which result in chemical weathering and are characterised by distinct decomposition of the parent rock's mineralogy. Conditions for the formation of deeply weathered regolith include a topographically moderate relief flat enough to allow leaching of

909-673: A strong wind from the south-east, known locally as the south-easter or the Cape Doctor , so called because it blows air pollution away. This wind is caused by a persistent high-pressure system over the South Atlantic to the west of Cape Town, known as the South Atlantic High , which shifts latitude seasonally, following the sun, and influencing the strength of the fronts and their northward reach. Cape Town receives about 3,100 hours of sunshine per year. Saprolite Conditions for

1010-529: Is Cape Point and the Cape of Good Hope . The peninsula forms the west side of False Bay and the Cape Flats. On the east side are the Helderberg and Hottentots Holland mountains. The three main rock formations are the late- Precambrian Malmesbury group (sedimentary and metamorphic rock), the Cape Granite suite, comprising the huge Peninsula, Kuilsriver-Helderberg, and Stellenbosch batholiths, that were intruded into

1111-486: Is due to prolonged erosion having carved out deep valleys, removing parts of the once continuous Table Mountain Group sandstone cover from the Cape Flats and False Bay, and leaving high residual mountain ridges. At times the sea covered the Cape Flats and Noordhoek valley and the Cape Peninsula was then a group of islands. During glacial periods the sea level dropped to expose the bottom of False Bay to weathering and erosion, with

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1212-413: Is fairly consistent over quite large areas, and the underwater landscape is often a continuation of the general trends above the surface, which can be useful for underwater navigational purposes. Table Mountain group sandstones were deposited on the eroded surface of granite and Malmesbury series basement, in the stream channels and tidal flats of a coastal plain and delta environment that extended across

1313-445: Is fairly flat. The origin of the hard sedimentary rocks of the ridges at Steenbras Deep, East Shoal and York shoal have not been identified. The pre-erosion section proposed by Compton suggests that these outcrops are likely to be from the basal Malmesbury group. Almost 50% of the Cape Peninsula and Cape Flats area is covered by weakly cemented marine sands. Sea-levels fluctuated between −120 and +200m from present mean sea level during

1414-544: Is more feldspathic and finer grained than the Skurweberg Formation , which is characterised by fairly thick bedded medium to coarse grained, light grey, slightly feldspathic quartzose sandstone. The Rietvlei Formation consists of alternating horizons of light grey quartzose and feldspathic sandstone, siltstone and shale. The formation of the Cape Fold Belt is the result of a collision of tectonic plates that ended over 200 million years ago The accumulated strata of

1515-401: Is possible to relatively date saprolite by considering that the saprolite must be younger than the parent material and older than any thick cover unit such a lava or sedimentary rock. This principle is useful in some contexts but in others, like certain parts of Sweden where grus is formed from Precambrian rocks and overlain by Quaternary deposits, it is of little value. The regolith of

1616-518: Is the valley of the Steenbras River, in which the Steenbras Dam was built as a water supply for Cape Town. The dam has been supplemented by several other dams around the western Cape, some of them considerably larger. This is almost entirely a conservation area, of high biodiversity. Bellville , Brackenfell , Durbanville , Kraaifontein , Goodwood and Parow are a few of the towns that make up

1717-452: Is within the city boundaries and there are several other nature reserves and marine-protected areas within, and adjacent to, the city, protecting the diverse terrestrial and marine natural environment. The earliest known remnants of human occupation in the region were found at Peers Cave in Fish Hoek and have been dated to between 15,000 and 12,000 years old. Various Khoikhoi groups notably

1818-533: The Anglo-Dutch Treaty of 1814 . The city became the capital of the newly formed Cape Colony , whose territory expanded very substantially through the 1800s, partially as a result of numerous wars with the amaXhosa on the colony's eastern frontier. In 1833 slavery was abolished in the colony freeing over 5500 slaves in the city, almost a third of the city's population at the time. The Convict Crisis of 1849, marked by substantial civil upheaval, bolstered

1919-695: The Cape Supergroup , of which parts of the Graafwater and Peninsula Formations remain, were uplifted between 280 and 21S million years ago, and were largely eroded away during the Mesozoic. The region was geologically stable during the Tertiary, which has led to slow denudation of the durable sandstones. Erosion rate and drainage has been influenced by fault lines and fractures, leaving remnant steep-sided massifs like Table Mountain surrounded by flatter slopes of deposits of

2020-557: The Khoikhoi clans who inhabited the area. In the late 16th century French, Danish, Dutch and English, but mainly Portuguese, ships regularly continued to stop over in Table Bay en route to the Indies. They traded tobacco, copper, and iron with the Khoikhoi clans of the region in exchange for fresh meat and other essential travelling provisions. In 1652, Jan van Riebeeck and other employees of

2121-521: The Northern Suburbs of Cape Town. In current popular culture these areas are often referred to as being beyond the " boerewors curtain," a play on the term " iron curtain ." UNESCO declared Robben Island in the Western Cape a World Heritage Site in 1999. Robben Island is located in Table Bay, some 6 km (3.7 mi) west of Bloubergstrand, a coastal suburb north of Cape Town, and stands some 30m above sea level. Robben Island has been used as

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2222-842: The Silurian period, and Rietvlei Formation from the Devonian period complete the Table Mountain group, and are found in the Hottentots Holland mountains to the East of False Bay. These strata are all well above the present sea level in the Cape Town area. The Cederberg Formation includes dark grey siltstone and silty sandstones, and is darker than the overlying Goudini Formation which is light brown to light grey quartzitic sandstone, with interbedded reddish brown siltstone and shale. The Goudini formation

2323-595: The Southern Suburbs , close to the mountains, rainfall is significantly higher and averages closer to 1,000 mm (39.4 in). Summer, which lasts from December to March, is warm and dry with an average maximum of 26 °C (79 °F) and minimum of 16 °C (61 °F). The region can get uncomfortably hot when the Berg Wind , meaning "mountain wind", blows from the Karoo interior. Spring and summer generally feature

2424-615: The Table Mountain group sandstones that were deposited on the eroded surface of the granite and Malmesbury series basement about 450 million years ago. The sand, silt and mud deposits were lithified by pressure and then folded during the Cape Orogeny to form the Cape Fold Belt , which extends in an arc along the western and southern coasts. The present landscape is due to prolonged erosion having carved out deep valleys, removing parts of

2525-919: The United East India Company ( Dutch : Verenigde Oost-indische Compagnie , VOC) were sent to the Cape Colony to establish a way-station for ships travelling to the Dutch East Indies , and the Fort de Goede Hoop (later replaced by the Castle of Good Hope ). The settlement grew slowly during this period, as it was hard to find adequate labour. This labour shortage prompted the local authorities to import enslaved people from Indonesia and Madagascar . Many of these people are ancestors of modern-day Cape Coloured and Cape Malay communities. Under Van Riebeeck and his successors, as VOC commanders and later governors at

2626-632: The Western Cape , but none of the others extend to the coastline in this area. The Stellenbosch pluton extends under the Helderberg and Hottentots Holland mountains. Cape Blue Rock, a dense Hornfels , was formed from the Malmesbury series rock by the Stellenbosch pluton, and was quarried as a building aggregate near Sir Lowry's Pass . The Blue Rock Quarry has been closed and is now flooded and used for water sports including diving and water skiing. Almost all

2727-508: The 19th century came to an end, the economic and political dominance of Cape Town in the Southern Africa region during the 19th century started to give way to the dominance of Johannesburg and Pretoria in the 20th century. In 1910, Britain established the Union of South Africa , which unified the Cape Colony with the two defeated Boer Republics and the British colony of Natal . Cape Town became

2828-434: The Atlantic Ocean with significant precipitation and strong north-westerly winds. Winter months in the city average a maximum of 18 °C (64 °F) and minimum of 8.5 °C (47 °F). Winters are snow and frost free, except on Table Mountain and on other mountain peaks, where light accumulation of snow and frost can sometimes occur. Total annual rainfall in the city averages 515 mm (20.3 in) although in

2929-447: The Cape Flats and leaving high residual mountain ridges in an example of inverted relief . Strike and dip vary considerably: on the Cape Peninsula dip is generally near to horizontal, so there are ledges rather than ridges, but on the east side of False Bay the dip is steep, often more than 45°, and where the strike is parallel to the shoreline (near Gordon's Bay and Rooi-els), this results in underwater ridges and gulleys also parallel to

3030-515: The Cape Supergroup and the older granites and Malmesbury group were raised and deformed by the pressure of the South American, Antarctic and African continental plates slowly moving together. The resulting fold mountains have been eroded to their present state over the ensuing period, and what exists today are the remnants of a much larger and higher mountain chain. Faults cut across and displace

3131-569: The Cape was considered a " Coloured labour preference area", to the exclusion of " Bantus ", i.e. Black Africans. The implementation of this policy was widely opposed by trade unions, civil society and opposition parties. It is notable that this policy was not advocated for by any Coloured political group, and its implementation was a unilateral decision by the apartheid government. During the student-led Soweto Uprising of June 1976, school students from Langa , Gugulethu and Nyanga in Cape Town reacted to

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3232-464: The Cape, a wide range of agricultural plants were introduced to the Cape. Some of these, including grapes, cereals, ground nuts, potatoes, apples and citrus, had a large and lasting influence on the societies and economies of the region. With the Dutch Republic being transformed into Revolutionary France 's vassal Batavian Republic , Great Britain moved to take control of Dutch colonies, including

3333-511: The Eastern side of False Bay from Gordon's Bay to Pringle Bay, e.g. at Die Kamer, Sandgat, Heuningkloof, Koeëlbaai, Blousteen, Rooiels and Drostersgat. Wave cut platforms at 18 to 20 m and at 30 m are well developed below Clarence Drive from Steenbras River Mouth to Koeëlbaai. On them rest rounded sandstone boulders, gravel and sand, up to a metre thick, often cemented by manganese and iron. In places scree partially overlies these deposits. In

3434-452: The False Bay coast evidence of higher stands of the sea is presented by wave cut platforms, benches, boulder-beach ridges, sea cliffs, caves and undercut ledges Wave cut caves, indicating former sea level stands between +4 and +8 m are found between Cape Point and Muizenberg at Rooikrans, Batsata cove, Blaasbalkgrot and Hell's Gate, among others. Even more spectacular wave-cut caves occur on

3535-571: The Gorinaiqua lived on these lands for thousands of years. Khoikhoi communities were some of the wealthiest groups in Africa and their lands and cattles would go on to build colonial Cape Town and the rest of South Africa. Bartolomeu Dias . Dias, the first European to reach the area, arrived in 1488 and named it "Cape of Storms" ( Cabo das Tormentas ). It was later renamed by John II of Portugal as " Cape of Good Hope " ( Cabo da Boa Esperança ) because of

3636-471: The Malmesbury Group about 630 million years ago, and the Table Mountain group sandstones that were deposited on the eroded surface of the granite and Malmesbury series basement about 450 million years ago. The sand, silt and mud deposits were lithified by pressure and then folded during the Cape Orogeny to form the Cape Fold Belt , which extends along the western and southern coasts. The present landscape

3737-479: The Pliocene and subsequent Pleistocene ice-age between 2 million and 15000 years ago as a result of fluctuating global temperature and variable amounts of water accumulated in polar ice caps. At times the sea covered the Cape Flats and Noordhoek valley and the Cape Peninsula was then a group of islands. Beach sands with shell fragments and estuarine muds were deposited and later overlain by calcrete-cemented dune sands as

3838-419: The Stellenbosch district. The Helderberg area of Greater Cape Town, previously known as the "Hottentots-Holland" area, is mostly residential, but also a wine-producing area east of the Cape Flats, west of the Hottentots Holland mountain range and south of the Helderberg mountain, from which it gets its current name. The Helderberg consists of the previous municipalities of Somerset West, Strand, Gordons Bay and

3939-566: The Stellenbosch granite pluton. The region includes the entire catchment of the Lourens and Sir Lowry's rivers, separated by the Schapenberg hill, and a small part of the catchment of the Eerste River to the west. The Helderberg is ecologically highly diverse, rivaling the Cape Peninsula, and has its own endemic ecoregions and several conservation areas. To the east of the Hottentots Holland mountains

4040-630: The Western Cape province. The official boundaries of the city proper extend between the City Bowl and the Atlantic Seaboard to the east and the Southern Suburbs to the south. The City of Cape Town , the metropolitan municipality that takes its name from the city covers the Greater Cape Town metropolitan area , known as the Cape Metropole, extending beyond the city proper itself to include

4141-491: The age of the land surface, tectonic activity, climate , climate history and the composition of the bedrock. Although these deeply weathered terrains now occur in a wide variety of climates ranging from warm humid to arid, tropical to temperate, they were formed under similar conditions in the past. In parts of Africa, India, South America, Australia and southeast Asia, regolith has been forming continuously for over 100 million years. Deeply weathered regoliths are widespread in

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4242-531: The balcony of Cape Town City Hall , hours after being released on 11 February 1990. His speech heralded the beginning of a new era for the country. The first democratic election , was held four years later, on 27 April 1994. Nobel Square in the Victoria & Alfred Waterfront features statues of South Africa's four Nobel Peace Prize winners: Albert Luthuli , Desmond Tutu , F. W. de Klerk and Nelson Mandela . Cape Town has undergone significant changes in

4343-556: The best governed province and city in the country. Of South Africa's 257 municipalities, only 38 received a clean financial audit in 2022 from the Auditor-General . Of those, 21 were in the Western Cape. The city's economy has diversified, with growth in sectors such as finance, real estate, and tourism. The establishment of the City Centre Improvement District (CCID) has been particularly successful in revitalizing

4444-507: The city center, bringing businesses and people back into the area. This initiative has transformed public spaces such as Greenmarket Square , Company's Garden , and St George's Mall, attracting both locals and tourists. In 2014, Cape Town was named World Design Capital of the Year. Cape Town was voted the best tourist destination in Africa at the 2023 World Travel Awards in Dubai and continues to be

4545-509: The city centre. The legacy of Apartheid means Cape Town remains one of the most racially segregated cities in South Africa. Many Black South Africans continue to live in informal settlements with limited access to basic services such as healthcare, education, and sanitation. The unemployment rate remains high at 23% (though nearly 10 points lower than the nationwide average), particularly among historically disadvantaged groups, and economic opportunities are unevenly distributed. Cape Town faced

4646-715: The colonial possessions of the VOC. Britain captured Cape Town in 1795 , but it was returned to the Dutch by treaty in 1803. British forces occupied the Cape again in 1806 following the Battle of Blaauwberg when the Batavian Republic allied with Britain's rival, France, during the Napoleonic Wars . Following the conclusion of the war Cape Town was permanently ceded to the United Kingdom in

4747-414: The deaths of 83 people. Since the 2010s, Cape Town and the wider Western Cape province have seen the rise of a small secessionist movement . Support for parties "which have formally adopted Cape independence" was around 5% in the 2021 municipal elections . Cape Town is located at latitude 33.55° S (approximately the same as Sydney and Buenos Aires and equivalent to Casablanca and Los Angeles in

4848-510: The dolerites are fine to medium grained, dark grey rocks with augite and plagioclase as major constituents. Quartz enriched variations of dolerite are found at Miller's Point , Llandudno and Chapman's Peak. Over the last 2 million years of the Quaternary geological period, cool glacial periods (hypothermals) about 100,000 years long, have been the norm. Canada and northern Eurasia were covered by continental ice sheets kilometres thick, and

4949-462: The earth, but have since then been exposed by prolonged erosion. The Peninsula batholith underlies the Cape Peninsula and the west side of False Bay, The Kuilsrivier-Helderberg batholith is to the northeast and the Stellenbosch batholith a bit further to the north. The characteristic spheroidal shapes of granite boulders are a result of preferential weathering along intersecting fractures and are well displayed around Llandudno and Simonstown . Close up,

5050-406: The east and joins the peninsula to the mainland. The Cape Town region is characterised by an extensive coastline, rugged mountain ranges, coastal plains and inland valleys. The extent of Cape Town has varied considerably over time. It originated as a small settlement at the foot of Table Mountain and has grown beyond its city limits as a metropolitan area to encompass the entire Cape Peninsula to

5151-607: The entire bottom of False Bay exposed. During this period an extensive system of dunes was formed on the sandy floor of False Bay. At this time the drainage outlets lay between Rocky Bank Cape Point to the west, and between Rocky Bank and Hangklip Ridge to the east, with the watershed roughly along the line of the contact zone east of Seal Island and Whittle Rock. Cape Town has a warm summer Mediterranean climate ( Köppen : Csb ), with mild, moderately wet winters and dry, warm summers. Winter, which lasts from June to September, may see large cold fronts entering for limited periods from

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5252-437: The entire bottom of False Bay exposed. During this period an extensive system of dunes was formed on the sandy floor of False Bay. The southward extensions of the now-buried Tertiary drainage must run east of Seal island, York Shoal and East Shoal in the north-central part of False Bay, and then down its central bathymetric deep axis towards the outlet between the submerged features of Rocky Bank and Hangklip Ridge. The bottom off

5353-547: The eroded material overlaying the older rocks, There are two internationally notable landmarks, Table Mountain and Cape Point , at opposite ends of the Peninsula Mountain Chain, with the Cape Flats and False Bay to the east and the Atlantic Ocean to the west. The landscape is dominated by sandstone plateaux and ridges, which generally drop steeply at their margins to the surrounding debris slopes, interrupted by

5454-492: The exposed granite has been extensively weathered and is in the form of rounded corestones. The colour is generally pale to medium grey, and the surface is typically fairly rough, with clearly visible crystals, and no layered structure. As an intrusive rock, dip and strike do not apply, but the massive rock is cracked on jointing planes, which tend to be characteristic of the location, and weathering has accentuated these joints. The general direction and spacing of joints in some areas

5555-443: The exposed shoreline Malmesbury rocks are steeply dipped, and weathered to form sharp edged ridges where more resistant layers stand out among the softer strata. The rocks are generally dark in colour where fresh rock has been exposed by erosion, and may be finely laminated. The Cape Granite suite is three huge batholiths that were intruded into the Malmesbury Group about 630 million years ago as molten rock and crystallised deep in

5656-668: The first European outpost at the Castle of Good Hope , becoming the economic and cultural hub of the Cape Colony . Until the Witwatersrand Gold Rush and the development of Johannesburg, Cape Town was the largest city in southern Africa. The metropolitan area has a long coastline on the Atlantic Ocean , which includes False Bay, and extends to the Hottentots Holland mountains to the east. The Table Mountain National Park

5757-499: The formation of deeply weathered regolith include a topographically moderate relief flat enough to prevent erosion and to allow leaching of the products of chemical weathering. A second condition is long periods of tectonic stability; tectonic activity and climate change can cause erosion. The third condition is humid tropical to temperate climate . Poorly weathered saprolite grit aquifers are capable of producing groundwater , often suitable for livestock. Deep weathering causes

5858-410: The formation of many secondary and supergene ores : bauxite , iron ores , saprolitic gold , supergene copper , uranium , and heavy minerals in residual accumulations. Saprolite (from Greek σαπρος = putrid + λιθος = rock) is a chemically weathered rock (literally, it means "rotten rock"). More intense weathering results in a continuous transition from saprolite to laterite . Saprolites form in

5959-445: The global effect was a lowering of sea level by some 130m because the sea was the source of the frozen water of these huge ice sheets. This means that False Bay and Table Bay were dry and covered by dunes for 90% of the last 2 million years. Warm interglacial periods (hyperthermals), have lasted only about 10 000 years and we are part way through the latest one which started about 6000 years ago. The coastline of False Bay, therefore,

6060-467: The granite is a coarse-grained rock consisting of large (2–5 cm) white or pink feldspar crystals, glassy brown quartz and flakes of black mica , and containing inclusions of dark Malmesbury hornfels near the contact zone. The climate of this region was warmer and wetter in the Cretaceous . This led to severe chemical weathering of the granite to saprolite rich in kaolin clays, decomposed from

6161-613: The great optimism engendered by the opening of a sea route to the Indian subcontinent and East Indies . In 1497, Portuguese explorer Vasco da Gama recorded a sighting of the Cape of Good Hope. In 1510, at the Battle of Salt River , the Portuguese admiral Francisco de Almeida and sixty-four of his men were killed and his party was defeated by the "Goringhaiqua" in Dutch approximate spelling) using cattle that were specially trained to respond to whistles and shouts. The Gorinaiqua were one of

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6262-581: The highest point of Table Mountain, at Maclear's Beacon and on parts of the Hottentots-Holland range. It contains clusters of angular boulders and pebbles and was deposited at a time when the Gondwana continent, of which Africa was a part, was situated close to the south pole. Graafwater, Peninsula and Pakhuis formations are from the Ordovician period. Cederberg , Goudini and Skurweberg Formations from

6363-504: The inter-tropical belt, particularly on the continental landmasses between latitudes 35°N and 35°S. Similar weathered regoliths exist at much higher latitudes – 35–42°S in southeast Australia (Victoria and Tasmania), 40–45°N in the United States (Oregon and Wisconsin) and 55°N in Europe (Northern Ireland, Germany) – although these are not regionally extensive. In some localities it

6464-407: The large visible crystals of potassium feldspar that are so conspicuous in the granite. The contact zone where the Malmesbury Group was intruded by molten granite can be seen at Sea Point and was made famous by Charles Darwin during his voyage of scientific discovery on H.M.S. Beagle in 1844. Here, slivers of dark coloured Malmesbury rocks, altered by intense heat are intermingled and folded with

6565-564: The largest in the Western Cape . The city is part of the City of Cape Town metropolitan municipality . The city is known for its harbour , its natural setting in the Cape Floristic Region , and for landmarks such as Table Mountain and Cape Point . In 2014, Cape Town was named the best place in the world to visit by The New York Times , and was similarly ranked number one by The Daily Telegraph in both 2016 and 2023. Located on

6666-499: The last major regression leaving the entire bottom of False Bay exposed. During this period an extensive system of dunes was formed on the sandy floor of False Bay. At this time the drainage outlets lay between Rocky Bank Cape Point to the west, and between Rocky Bank and Hangklip Ridge to the east. The late- Precambrian age Malmesbury Group is the oldest rock formation in the area, consisting of alternating layers of dark grey fine-grained greywacke , sandstone and slate , seen along

6767-407: The legislative capital of the Union, and later of the Republic of South Africa . By the time of the 1936 census , Johannesburg had overtaken Cape Town as the largest city in the country. In 1945 the expansion of the Cape Town foreshore was completed adding an additional 194 ha (480 acres) to the City Bowl area to the city centre. Prior to the mid-twentieth century, Cape Town was one of

6868-741: The lower zones of soil horizons and represent deep weathering of the bedrock surface. In lateritic regoliths – regoliths are the loose layer of rocks that rest on the bedrock – saprolite may be overlain by upper horizons of residual laterite; most of the original profile is preserved by residual soils or transported overburden. Weathering formed thin kaolinitic [Al 2 Si 2 O 5 (OH) 4 ] saprolites 1,000 to 500 million years ago; thick kaolinitic saprolites 200 to 66 million years ago; and medium-thick immature saprolites 5 million years ago in Sweden. The general structure of kaolinite has silicate [Si 2 O 5 ] sheets bonded to aluminium hydroxide [Al 2 (OH) 4 ] layers. Iron compounds are

6969-418: The matrix of the plug, cut both agglomerate and adjacent granite There are a number of dolerite dykes in the region, some of which are visible at the coast. These dykes are intrusive to the Cape Granite Suite and pre-Cape sedimentary rocks, and in some places also the Graafwater and Peninsula formations. They vary in width from a fraction of a metre to as much as 22 m at Logies Bay, Llandudno. Most of

7070-441: The more sheltered Simon's Bay. The east side of False Bay also has extensive areas of fine quartzitic sand bottom, and there are also occasional deposits of a very fine low density silty material which is easily disturbed and returned to suspension. This silt generally deposits over the sand and depressions in the reef during relatively long periods of calm seas. There are small areas of shelly gravel and mud near Gordon's Bay between

7171-400: The most important tourist destination in the country. Cape Town has been named the best travel city in the world every year since 2013 in the Telegraph Travel Awards. The legacy of apartheid's spatial planning is still evident, with significant disparities between affluent areas and impoverished townships . 60% of the city's population live in townships and informal settlements far from

7272-751: The most racially integrated cities in South Africa. In the 1948 national elections , the National Party won on a platform of apartheid (racial segregation) under the slogan of " swart gevaar " (Afrikaans for "black danger"). This led to the erosion and eventual abolition of the Cape's multiracial franchise . In 1950, the apartheid government first introduced the Group Areas Act , which classified and segregated urban areas according to race. Formerly multi-racial suburbs of Cape Town were either purged of residents deemed unlawful by apartheid legislation, or demolished. The most infamous example of this in Cape Town

7373-553: The most unstable minerals in humid, oxidizing environments; many cadmium , cobalt , copper , molybdenum , nickel and zinc sulfides are easily leached to deep in the profile. Carbonates are highly soluble, especially in acidic environments; the elements hosted by them – calcium, magnesium, manganese and strontium – are strongly leached. Serpentinite – oxidized and hydrolized low-silicon, iron- and magnesium-rich oxide igneous rocks – are progressively weathered through this zone. Ferromagnesian minerals are

7474-537: The mountain. To the immediate south of the city, the Cape Peninsula is a scenic mountainous spine jutting 40 km (25 mi) southward into the Atlantic Ocean and terminating at Cape Point . There are over 70 peaks above 300 m (980 ft) within Cape Town's official metropolitan limits . Many of the city's suburbs lie on the large plain called the Cape Flats , which extends over 50 km (30 mi) to

7575-399: The news of the protests against Bantu Education by organising gatherings and marches of their own. A number of school buildings were burnt down and the protest action was met with forceful resistance from the police. Cape Town has been home to many leaders of the anti-apartheid movement . In Table Bay , 10 km (6 mi) from the city is Robben Island . This penitentiary island was

7676-432: The north to Cape Point in the south, with an area of about 470 km (180 sq mi), and it displays more topographical variety than other similar sized areas in southern Africa, and consequently spectacular scenery. There are diverse low-nutrient soils, large rocky outcrops, scree slopes, a mainly rocky coastline with embayed beaches, and considerable local variation in climatic conditions. The sedimentary rocks of

7777-498: The northern hemisphere) and longitude 18.25° E. Table Mountain , with its near vertical cliffs and flat-topped summit over 1,000 m (3,300 ft) high, and with Devil's Peak and Lion's Head on either side, together form a dramatic mountainous backdrop enclosing the central area of Cape Town, the so-called City Bowl . A thin strip of cloud, known colloquially as the "tablecloth" ("Karos" in Afrikaans ), sometimes forms on top of

7878-402: The once continuous Table Mountain Group sandstone cover from over the Cape Flats and False Bay, and leaving high residual mountain ridges. At times the sea covered the Cape Flats and Noordhoek valley and the Cape Peninsula was then a group of islands. During glacial periods the sea level dropped to expose the bottom of False Bay to weathering and erosion, with the last major regression leaving

7979-537: The pale coloured intrusive granite to form a complex mixed rock. Large feldspar crystals occur in both the granite and dark hornfels layers Though initially intruded at great depth, prolonged erosion eventually exposed the granite at the surface and it and what remains of the similarly eroded Malmesbury group now form a basement upon which younger sedimentary rocks of the Table Mountain Group were deposited. Other large granite plutons of similar age are found in

8080-403: The primary coloring agents in saprolites. At most outcrops the color comes from ferric compounds; the color relates to the mineralogy and particle size. Submicron-sized goethite [FeO(OH)] is yellow; coarse goethite is brown. Sub-micron-sized hematite [Fe 2 O 3 ] is red; coarse hematite is gray to black. Regoliths vary from a few meters to over 150 m (490 ft) thick, depending on

8181-544: The principal hosts for nickel, cobalt, copper and zinc in sulfide-poor mafic and ultramafic rocks, and are retained higher in the profile than sulfide-hosted metals. They are leached from the upper horizons and reprecipitate with secondary iron-manganese oxides in the mid- to lower saprolite. Aquifers in Western Australia are of saprolite grit. Poorly weathered saprolite grit aquifers are capable of producing groundwater, often suitable for livestock. Yields depend on

8282-521: The products of chemical weathering. A second condition is long periods of tectonic stability; tectonic activity and climate change partially erode the regolith. Weathering rates of 20 m (66 ft) per million years suggest that deep regoliths require several million years to develop. The third condition is humid tropical to temperate climate; higher temperatures enable reactions to occur more rapidly. Deep weathering can occur in cooler climates, but over longer periods of time. Sulfides are some of

8383-469: The push for self-governance in the Cape. With expansion came calls for greater independence from the UK, with the Cape attaining its own parliament (1854) and a locally accountable Prime Minister (1872). Suffrage was established according to the non-racial Cape Qualified Franchise . During the 1850s and 1860s, additional plant species were introduced from Australia by the British authorities. Notably rooikrans

8484-524: The region about 450 million years ago. The sand, silt and mud deposits were lithified by pressure and then folded during the Cape Orogeny to form the Cape Fold Belt , which extends along the western and southern coasts. The basal Graafwater Formation (300-450m thick) consists of interlayered pale brown sandstone, laminated pink siltstone and dark maroon coloured shale . Closer examination shows deposition cycles from current-bedded channel sandstones to increasing proportions of fine-grained maroon shales at

8585-478: The rock layers. These more easily eroded zones are marked by ravines; cross-cutting faults separate multiple peaks of the Twelve Apostles. Some fault zones of crushed rock (breccia) are re-cemented by dark brown coloured iron and manganese oxide minerals. The present landscape is due to prolonged erosion having carved out deep valleys, removing parts of the once continuous Table Mountain Group sandstone cover from

8686-615: The rocky Sea Point and Bloubergstrand shorelines, and from the Strand to Gordon's Bay . These sediments were originally deposited on an ancient continental slope by submarine slumping and turbidity currents . The sequence was subsequently metamorphosed by heat and pressure and folded tightly in a NW direction during the Saldanian orogeny so that the rock layers are now almost vertical. These rocks were, in most places, scoured by wave action during past periods of higher sea level. Most of

8787-473: The rocky shoreline reef and the sand bottom. Gravel beds underlying raised-beach terraces occur intermittently along most of the coastline. Boulder beds are found almost continuously from Kommetjie southwards to Cape Point. They rest on a terrace, 7 to 10 m above sea level, which cuts into Table Mountain Sandstone. There are indications of an older raised pebble beach at 17 to 20 m here as well. Along

8888-697: The same vicinity raised boulder beaches, similar to those on the peninsula, occur at 3 to 5 m above sea level. On the False Bay coast just below the old lighthouse at Cape Point, a basic agglomerate plug intrudes course grained porphyritic granite. This outcrop is unconformably overlain by sediments of the Table Mountain group. It consists of a heterogeneous mass of dark green to grey basic rock with red-brown specks that enclose randomly oriented clasts of variable size up to 300 mm. The clasts consist of rounded and angular quartzose sandstone, siltstone, hornfels, porphyritic granite, basic rocks and fine-grained reddish granite. Basic dykes of similar lithology to

8989-434: The sea retreated. "Dune rock" that was deposited during a Pleistocene interglacial period about 120,000 years ago is now being eroded in the sea-cliffs near Swartklip. During glacial periods the sea level dropped to expose the bottom of False Bay to weathering and erosion. The last major regression, about 20,000 years ago, lowered the sea level to the present 130m isobath, which is south of Cape Point and Cape Hangklip, leaving

9090-693: The shore of Table Bay , the City Bowl area of Cape Town is the oldest urban area in the Western Cape , with a significant cultural heritage. It was founded by the Dutch East India Company (VOC) as a supply station for Dutch ships sailing to East Africa , India , and the Far East . Jan van Riebeeck 's arrival on 6 April 1652 established the VOC Cape Colony , the first permanent European settlement in South Africa. Cape Town outgrew its original purpose as

9191-402: The shoreline, and usually interrupted by transverse gullies which are extensions of gullies extending above the water. In other places the ridges are at a greater angle to the shoreline. The offshore reef at Steenbras Deep is relatively flat topped, the strike is roughly north–south and dip is quite steep. The extensive shoal at Rocky Bank is relatively flat topped, with steps, and here the dip

9292-479: The site of a maximum security prison where many famous apartheird-era political prisoners served long prison sentences. Famous prisoners include activist, lawyer and future president Nelson Mandela who served 18 of his 27 years of imprisonment on the island, as well as two other future presidents, Kgalema Motlanthe and Jacob Zuma . In one of the most famous moments marking the end of apartheid, Nelson Mandela made his first public speech since his imprisonment, from

9393-558: The south, the Cape Flats , the Helderberg basin and part of the Steenbras catchment area to the east, and the Tygerberg hills, Blouberg and other areas to the north. Robben Island in Table Bay is also part of Cape Town. It is bounded by the Atlantic Ocean to the west, and False Bay to the south. To the north and east, the extent is demarcated by boundaries of neighbouring municipalities within

9494-403: The texture of the materials and their depth from which the aquifer is derived. The distributions of gold and calcium carbonate or calcium magnesium carbonates are closely correlated and documented in the southern Yilgarn Craton , Western Australia, in the top 1 to 2 m (3.3 to 6.6 ft) of the soil profile and locally as deep as 5 m (16 ft). The gold-carbonate association

9595-421: The top, deposited in flood plains and lagoons. The Peninsula Formation (800-1500m thick) consisting of hard, light grey medium to coarse grained pebbly quartz sandstone, dominates the steep mountain cliffs. Current bedding and pebble layers suggest that it was originally deposited as migrating sand bars in broad river channels. The Pakhuis Formation tillite (a lithified glacial outwash gravel) occurs on

9696-493: The west coast of the cape Peninsula between and beyond the rocky reef areas is largely fairly fine white quartzitic sand with some areas of coarser shelly sand. The bottom sediments of False Bay are more varied. On the west side of the bay there is a general tendency towards fine to medium quartzitic sand and coarser calcareous material, mostly mollusc shell fragments, with patches of a maerl of branching coralline algae fragments. There are also areas of very fine sand, almost mud, in

9797-411: The west side of False Bay and the Cape Flats. On the east side are the Helderberg and Hottentots Holland mountains. The three main rock formations are the late- Precambrian Malmebury group (sedimentary and metamorphic rock), the Cape Granite suit, comprising the huge Peninsula, Kuilsrivier-Helderberg, and Stellenbosch batholiths, that were intruded into the Malmesbury Group about 630 million years ago, and

9898-479: The years since Apartheid. Cape Town has experienced economic growth and development in the post-apartheid era. The city has become a major economic hub in South Africa, attracting international investment and tourism. The Democratic Alliance (DA), a liberal political party which came to power in Cape Town in 2006, has been credited with improving bureaucratic efficiency, public safety and fostering economic development. Opinion polls show that South Africans see it as

9999-600: Was introduced to stabilise the sand of the Cape Flats to allow for a road connecting the peninsula with the rest of the African continent and eucalyptus was used to drain marshes. In 1859 the first railway line was built by the Cape Government Railways and a system of railways rapidly expanded in the 1870s. The discovery of diamonds in Griqualand West in 1867, and the Witwatersrand Gold Rush in 1886, prompted

10100-486: Was the suburb of District Six . After it was declared a whites-only area in 1965, all housing there was demolished and over 60,000 residents were forcibly removed. Many of these residents were relocated to the Cape Flats . The earliest of the Cape Flats forced removals saw the expulsion of Black South Africans to the Langa , Cape Town's first and oldest township, in line with the 1923 Native Urban Areas Act . Under apartheid,

10201-462: Was usually across the mouth of the present False Bay. Robben Island was a hill on a coastal plain with the coast west of the island for most of the past 2 million years. Cape Town Cape Town is the legislative capital of South Africa . It is the country's oldest city and the seat of the Parliament of South Africa . It is the country's second-largest city, after Johannesburg , and

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