's
Sentinel-2 Adelaide is north of the Fleurieu Peninsula, on the Adelaide Plains between the Gulf St Vincent and the relatively low-lying Mount Lofty Ranges (Mount Lofty, the highest point, is 710 metres above sea level). The city stretches from the coast to the foothills, and from
Gawler at its northern extent to
Sellicks Beach in the south. According to Regional Development Australia, an Australian government planning initiative, the "Adelaide Metropolitan Region" has a total land area of , while a more expansive definition by the Australian Bureau of Statistics defines a "Greater Adelaide" statistical area totalling . Much of Adelaide was bushland before British settlement, with some variation – sandhills, swamps and marshlands were prevalent around the coast. The loss of the sandhills to urban development had a particularly destructive effect on the coastline due to erosion. Where practical, the government has implemented programs to rebuild and vegetate sandhills at several of Adelaide's beachside suburbs.
Tennyson Dunes is the largest contiguous, tertiary dune system contained entirely within Metropolitan Adelaide, providing refuge for a variety of remnant species formerly found along the entire coastline. Much of the original vegetation has been cleared with what is left to be found in reserves such as the
Cleland National Park and
Belair National Park. A number of creeks and rivers flow through the Adelaide region. The largest are the Torrens and
Onkaparinga catchments. Adelaide relies on its many reservoirs for water supply with the
Happy Valley Reservoir supplying around 40% and the much larger
Mount Bold Reservoir 10% of Adelaide's domestic requirements respectively.
Geology Adelaide and its surrounding area is one of the most seismically active regions in Australia. On 1 March 1954 at 3:40 am Adelaide experienced its largest recorded earthquake to date, with the epicentre 12 km from the city centre at
Darlington, and a reported magnitude of 5.6. There have been smaller earthquakes in 2010, 2011, 2014, 2017, 2018 and 2022. The uplands of the
Adelaide Hills, part of the southern
Mount Lofty Ranges to the east of Adelaide, are defined on their western side by a number of arcuate faults (the Para, Eden, Clarendon and Willunga Faults), and consist of rocks such as
siltstone,
dolomite and
quartzite, dating from the
Neoproterozoic to the middle
Cambrian, laid down in the Adelaide Rift Complex, the oldest part of the
Adelaide Superbasin. Most of the Adelaide metropolitan area lies in the downthrown St Vincent Basin and its embayments, including the
Adelaide Plains Sub-basin, and the Golden Grove, Noarlunga and Willunga Embayments. These basins contain deposits of
Tertiary marine and non-marine sands and limestones, which form important aquifers. These deposits are overlain by
Quaternary alluvial fans and
piedmont slope deposits, derived from erosion of the uplands, consisting of sands, clays and gravels, interfingering to the west with
transgressive Pleistocene to
Holocene marine sands and coastal sediments of the shoreline of Gulf St Vincent.
Urban layout Adelaide is a planned city, designed by the first Surveyor-General of South Australia, Colonel
William Light. His plan, sometimes referred to as "Light's Vision" (also the name of a statue of him on
Montefiore Hill), arranged Adelaide in a
grid, with
five squares in the
Adelaide city centre and a ring of parks, known as the
Adelaide Parklands, surrounding it. Light's selection of the location for the city was initially unpopular with the early settlers, as well as South Australia's first governor, John Hindmarsh, due to its distance from the harbour at Port Adelaide, and the lack of fresh water there. was built on a
grid plan, known as "Light's Vision". Light successfully persisted with his choice of location against this initial opposition. Recent evidence suggests that Light worked closely with George Kingston as well as a team of men to set out Adelaide, using various templates for city plans going back to
Ancient Greece, including
Italian Renaissance designs and the similar layouts of the American cities
Philadelphia and
Savannah–which, like Adelaide, follow the same layout of a central city square, four complementing city squares surrounding it and a parklands area that surrounds the city centre. , one of the five main squares in the city centre and considered the heart of Adelaide's
grid layout The benefits of Light's design are numerous: Adelaide has had wide multi-lane roads from its beginning, an easily navigable
cardinal direction grid layout and an expansive green ring around the city centre. There are two sets of
ring roads in Adelaide that have resulted from the original design. The
inner ring route (
A21) borders the parklands, and the outer route (A3/
A13/
A16/
A17) completely bypasses the inner city via (in clockwise order)
Grand Junction Road, Hampstead Road, Ascot Avenue,
Portrush Road, Cross Road and
South Road. Suburban expansion has to some extent outgrown Light's original plan. Numerous former outlying villages and "country towns", as well as the satellite city of
Elizabeth, have been enveloped by its
suburban sprawl. Expanding developments in the Adelaide Hills region led to the construction of the
South Eastern Freeway to cope with growth, which has subsequently led to new developments and further improvements to that transport corridor. Similarly, the booming development in Adelaide's
South led to the construction of the
Southern Expressway. New roads are not the only transport infrastructure developed to cope with the urban growth. The
O-Bahn Busway and Adelaide Metro are examples of a unique solution to
Tea Tree Gully's transport woes in the 1980s. The development of the nearby suburb of
Golden Grove in the late 1980s followed a planned approach to urban growth. In the 1960s, a
Metropolitan Adelaide Transport Study Plan was proposed to cater for the future growth of the city. The plan involved the construction of freeways,
expressways and the upgrade of certain aspects of the public transport system. The then premier
Steele Hall approved many parts of the plan and the government went as far as purchasing land for the project. The later
Labor government elected under
Don Dunstan shelved the plan, but allowed the purchased land to remain vacant, should the future need for freeways arise. In 1980, the
Liberal party won government and premier
David Tonkin committed his government to selling off the land acquired for the MATS plan, ensuring that even when needs changed, the construction of most MATS-proposed freeways would be impractical. Some parts of this land have been used for transport, (e.g. the O-Bahn Busway and Southern Expressway), while most has been progressively subdivided for residential use. In 2008, the
SA Government announced plans for a network of
transport-oriented developments across the Adelaide metropolitan area and purchased a
10 hectare industrial site at
Bowden for $52.5 million as the first of these developments.
Housing Historically, Adelaide's suburban residential areas have been characterised by single-storey detached houses built on blocks. A relative lack of suitable, locally available timber for construction purposes led to the early development of a brick-making industry, as well as the use of stone, for houses and other buildings. By 1891, 68% of houses were built of stone, 15% of timber, and 10% of brick, with brick also being widely used in stone houses for quoins, door and window surrounds, and chimneys and fireplaces. There is a wide variety in the styles of these houses. Until the 1960s, most of the more substantial houses were built of red brick, though many front walls were of ornamental stone. Then cream bricks became fashionable, and in the 1970s, deep red and brown bricks became popular. Until the 1970s, roofs tended to be clad with (painted)
corrugated iron or cement or clay tiles, usually red "terracotta". Since then,
Colorbond corrugated steel has dominated. Most roofs are pitched. Flat roofs are not common. to cope with Adelaide's
reactive soils, particularly Keswick Clay, black earth and some red-brown earth soils. The use of precast concrete panels for floor and wall construction has also increased. The city has hot, dry summers and cool winters with moderate rainfall. Most rain falls in the winter months, leading to the suggestion that the climate be classified as a "cold monsoon". Rainfall is unreliable, light and infrequent throughout summer, although heavy falls can occur. The winter has fairly reliable rainfall with June being the wettest month of the year, averaging around 80 mm.
Frosts are occasional, with the most notable occurrences in 1908 and 1982. Hail may occur in winter. Adelaide is a windy city with significant
wind chill in winter, which makes the temperature
seem colder than it actually is. Snowfall in the metropolitan area is extremely rare, although light and sporadic falls in the nearby hills and at
Mount Lofty occur during winter. Dewpoints in the summer typically range from . There are usually several days in summer where the temperature reaches or above. While conditions vary from year-to-year, a warming trend has been
increasing in recent years, and with drought conditions experienced in SA in 2024−25, Adelaide has had to rely on
desalination to augment its water supply. Temperature extremes range from −2.6 °C (31.4 °F), 8 June 1982 to 47.7 °C (117.9 °F), 24 January 2019. The city features 90.6 clear days annually. The average sea temperature ranges from in August to in February.
Liveability in autumn Adelaide was consistently ranked in the world's 10
most liveable cities through the 2010s by
The Economist Intelligence Unit. In June 2021,
The Economist ranked Adelaide the third most liveable city in the world, behind
Auckland and
Osaka. In June 2023, Adelaide was ranked the twelfth most liveable city in the world by the Economist Intelligence Unit. In December 2021, Adelaide was named the world's second National Park City, after the state government had lobbied for this title. It was ranked the
most liveable city in Australia by the
Property Council of Australia, based on surveys of residents' views of their own city, between 2010 and 2013, dropping to second place in 2014. == Governance ==