Australia is an island continent located in the Southern Hemisphere. Neighbouring countries to the north include Indonesia, East Timor and Papua New Guinea, the Solomon Islands, Vanuatu and New Caledonia to the northeast, and New Zealand to the southeast.
The Australian continent has been inhabited by Indigenous Australians for an estimated 40,000 years. Following seasonal visits by Malay fishermen from the north and by 17th century European explorers and merchants, the eastern half of the continent was in 1770 claimed by the British. Officially settled as the penal colony of New South Wales on 26 January 1788, a further five largely self-governing colonies were successively established in Australia as the population grew and new areas were explored during the 19th century. In 1901, six colonies covering the continent federated and the Commonwealth of Australia was established. The capital city is Canberra, and the current population of around 20 million is concentrated in the large coastal cities of Sydney, Melbourne, Brisbane, Perth, and Adelaide.
The name Australia derives from the Latin word "australis" meaning "of the south". References to an "unknown southern land" (Terra Australis Incognita) are found as far back as Roman times, and were also common in mediaeval geography. The word "australische" was used as early as 1638 by Dutch officials in Batavia to refer to the newly discovered land to the south, while the first recorded use of the word "Australia" in English is in 1693, in a translation of a French novel penned in 1692.
Australia has an area of 7,686,850 square kilometres, and is surrounded by the Indian, Southern and Pacific oceans. The continent is separated from Asia by the relatively narrow Arafura and Timor seas. Australia's coastline totals some 25,760 kilometres.
The world's largest coral reef, the Great Barrier Reef, is located a short distance off the north-east coast and extends for over 2,000 kilometres. The world's largest monolith, Mount Augustus, is located in Western Australia, while the better known and iconic Uluru (Ayers Rock) monolith is located in the Northern Territory. Mount Kosciuszko on the Great Dividing Range is the highest mountain in Australia at 2,228 metres.
Around 75% of Australia is desert or semi-arid, and Australia is the driest inhabited continent in the world. It is also the flattest, and has the oldest and least fertile soils. Temperate climates are found only the south-east and south-west corners of the continent and in the large island of Tasmania. The northern part of the country has a tropical climate and vegetation consisting of rainforest, woodland, and grasslands. Several deserts including the Simpson Desert, Gibson Desert, Great Sandy Desert, Great Victoria Desert and the Tanami Desert are located in the central and western regions of the continent.