Coral Sea Islands

The continent of Australia, sometimes known in technical contexts as Sahul (/səˈhuːl/), Australia-New Guinea, Australinea, or Meganesia to distinguish it from the country of Australia, is located within the Southern and Eastern hemispheres, near the Maritime Southeast Asia. The continent includes mainland Australia, Tasmania, the island of New Guinea (Papua New Guinea and Western New Guinea), the Aru Islands, the Ashmore and Cartier Islands, most of the Coral Sea Islands, and some other nearby islands. Situated in the geographical region of Oceania, more specifically in the subregion of Australasia, Australia is the smallest of the seven traditional continents.

The continent includes a continental shelf overlain by shallow seas which divide it into several landmasses—the Arafura Sea and Torres Strait between mainland Australia and New Guinea, and Bass Strait between mainland Australia and Tasmania. When sea levels were lower during the Pleistocene ice age, including the Last Glacial Maximum about 18,000 BC, they were connected by dry land into the combined landmass of Sahul. The name "Sahul" derives from the Sahul Shelf, which is a part of the continental shelf of the Australian continent. During the past 18,000 to 10,000 years, rising sea levels overflowed the lowlands and separated the continent into today's low-lying arid to semi-arid mainland and the two mountainous islands of New Guinea and Tasmania. With a total land area of 8.56 million square kilometres (3,310,000 sq mi), the Australian continent is the smallest, lowest, flattest, and second-driest continent (after Antarctica) on Earth. As the country of Australia is mostly on a single landmass, and comprises most of the continent, it is sometimes informally referred to as an island continent, surrounded by oceans.

The states and territories are the national subdivisions and second level of government of Australia. The states are partially sovereign, administrative divisions that are self-governing polities, having ceded some sovereign rights to the federal government. They have their own constitutions, legislatures, executive governments, judiciaries and law enforcement agencies that administer and deliver public policies and programs. Territories can be autonomous and administer local policies and programs much like the states in practice, but are still legally subordinate to the federal government.

Australia has six federated states: New South Wales (including Lord Howe Island), Queensland, South Australia, Tasmania (including Macquarie Island), Victoria, and Western Australia. Australia also has ten federal territories, out of which three are internal territories: the Australian Capital Territory, the Jervis Bay Territory, and the Northern Territory on the Australian mainland; and seven are external territories: the Ashmore and Cartier Islands, the Australian Antarctic Territory, Christmas Island, the Cocos (Keeling) Islands, the Coral Sea Islands, Heard Island and McDonald Islands, and Norfolk Island that are offshore dependent territories. Every state and internal territory (except the Jervis Bay Territory) is self-governing with its own independent executive government, legislature, and judicial system, while the rest only have local government status overseen by federal departments.

This is a list of countries and territories by the United Nations geoscheme, including 193 UN member states, two UN observer states (the Holy See and Palestine), two states in free association with New Zealand (the Cook Islands and Niue), and 49 non-sovereign dependencies or territories, as well as Western Sahara (a disputed territory whose sovereignty is contested) and Antarctica.

In total, 248 countries and territories have been listed. Not included in the list are eight de facto states (whose sovereignty are not recognised by the United Nations), the Sovereign Base Areas of Akrotiri and Dhekelia (SBA), and four uninhabited territories (the Ashmore and Cartier Islands, Clipperton Island, the Coral Sea Islands, and Navassa Island).

Willis Island is the only permanently inhabited island in the Coral Sea Islands Territory, an external territory of Australia, located beyond the Great Barrier Reef in the Coral Sea. The island is located some 450 kilometres (280 mi) east of Cairns, Queensland. It is the southernmost of the Willis Islets, a group of three islands which with their associated sandy cays stretch in a NNE to SSW line for about 12 kilometres (7.5 mi). Willis Island itself is aligned NW to SE and is about 500 metres (1,600 ft) long by 150 metres (490 ft) wide, 7.7 hectares (19 acres) in area, rising to about 9 metres (30 ft) above sea level.

13°54′29″S 146°36′55″E / 13.90806°S 146.61528°E / -13.90806; 146.61528

Osprey Reef is a submerged atoll in the Coral Sea, northeast of Queensland, Australia. It is part of the Northwestern Group of the Coral Sea Islands. Osprey Reef is roughly oval in shape, measuring 25 by 12 kilometres (16 by 7 mi), and covers around 195 square kilometres (75 sq mi). It has a perimeter of 69.5 kilometres (43.2 mi). The central lagoon is only 30 metres (98 ft) deep.

Cato Reef, a part of Cato Bank, is a coral reef in the Coral Sea, off the central coast of Queensland, Australia.