Adelaide city centre (Kaurna: Tarndanya)^[3] is the inner city locality of Greater Adelaide, the capital city of South Australia. It is known by locals simply as "the City" or "Town" to distinguish it from Greater Adelaide and from the City of Adelaide local government area (which also includes North Adelaide and from the Park Lands around the whole city centre). The population was 15,115 in the 2016 census.

Adelaide city centre was planned in 1837 on a greenfield site following a grid layout, with streets running at right angles to each other. It covers an area of 4.33 square kilometres (1.67 square miles) and is surrounded by 6.68 square kilometres (2.58 square miles) of park lands.^{[4][note 1]} Within the city are five parks: Victoria Square in the exact centre and four other, smaller parks.

Names for elements of the city centre are as follows:

• The "city square mile" (in reality 1.67 square miles or 4.33 square kilometres) is the constructed area bordered by North, East, South and West Terraces.
• The "central business district" (CBD) is an alternative term, but more accurately describes the intensively developed northern half of the city, which contains a multitude of commercial, cultural and entertainment premises, restaurants and high-rise apartments. The southern, lower-density half mainly contains small businesses, restaurants and, residentially, a mix of mansions, houses and conserved 19th century cottages, and (fewer) high-rise apartments.
• Precincts such as the West End and the East End have distinctive characters. CBD shopping precincts include Rundle Mall and Adelaide Central Market.
• In what is often described as the "North Terrace cultural precinct", many educational, cultural, entertainment and medical institutions lie between the northern side of North Terrace and the River Torrens – notably university campuses, the Adelaide Festival Centre, and the Parliament of South Australia. Adelaide railway station is also located there.

Before the British colonisation of South Australia, the Adelaide Plains, on which Adelaide was built, were home to the Kaurna group of Aboriginal Australians. The colony of South Australia was established in 1836 at Glenelg, and the city itself established in 1837. The location and characteristic grid layout of the city and North Adelaide, as well as the surrounding parklands, were the result of the work of Colonel William Light (1786–1839), who was the first Surveyor General of South Australia. The area where the Adelaide city centre now exists was once known as "Tarndanya",^[5] the Kaurna word for as "male red kangaroo rock", which was the name used for an area along the south bank of what is now known as the River Torrens (Karrawiri Pari), which flows through Adelaide.

Adelaide was not as badly affected by the 1860s economic depression in Australia as other gold rush cities like Sydney and Melbourne, allowing it to prosper. Historian F.W. Crowley noted that the city was full of elite upper-class citizens which provided a stark contrast to the grinding poverty of the labour areas and slums outside the inner city ring. Due to its historic wealth during the 20th century, the city retains a notable portion of Victorian architecture.^{[citation needed]}

Adelaide is separated from its greater metropolitan area by a ring of public parklands on all sides. The so-called "square mile" within the park lands is defined by a small area of high rise office and apartment buildings in the centre north, around King William Street, which runs north-to-south through the centre. Surrounding this central business district are a large number of medium to low density apartments, townhouses and detached houses which make up the residential portion of the city centre.

The population was 15,115 in the 2016 census in the Adelaide city centre, 38.8 percent born in Australia.^[23] The next most common countries of birth were China 17.5%, Malaysia 4.4%, England 3.4%, Hong Kong 2.8% and India 1.9%. 44.6% of people spoke only English at home. Other languages spoken at home included Mandarin 19.6%, Cantonese 4.9%, Arabic 1.9%, Korean 1.9% and Vietnamese 1.1%. The most common response for religion in Adelaide was 'No Religion' at 47.7% of the population.^[23]

At federal level, Adelaide is within the Division of Adelaide, a marginal seat which historically has alternated between the Liberal and Labor parties. It has been held since 2019 by Steve Georganas of the Labor party.^[24]

In the South Australian House of Assembly, Adelaide is within the Electoral district of Adelaide. Since the March 2022 state election, the seat has been held by Lucy Hood of the Labor party.

Adelaide's cultural and entertainment precincts/venues are generally concentrated in the city centre. They include the Convention Centre, Entertainment Centre and the redeveloped Adelaide Oval. Additionally, most of the events relating to the Adelaide Festival and Adelaide Fringe are held within Adelaide's city centre during February and March. This time is known as "Mad March", due to the large number of other cultural festivities at the same time, including the Adelaide 500 and WOMADelaide. North Terrace is considered Adelaide's "cultural boulevard" because of its tight concentration of galleries and museums.

• Aerial view of the Adelaide city centre looking south-east, 2005.
• A statue of Queen Victoria has stood in the geometric centre of both Victoria Square and "the square mile" since 1894.
• Part of North Terrace, 2009.
• Adelaide CBD from above, 2022.
• High rise buildings on Hindmarsh Square, 2012.
• Night aerial of the CBD, 2014
• Statue of King Edward VII on North Terrace.
• St Francis Xavier's Cathedral, Victoria Square.
• Brookman Building on North Terrace, part of the City East campus of the University of South Australia
• Rundle Street looking east

• Adelaide (Greater Adelaide metropolis)
• City of Adelaide (local government area)
• North Adelaide
• Street art in Adelaide
• Grid layout