Greenland (both larger) are generally considered to be continental landmasses rather than islands. Three-quarters of Greenland is covered by the only permanent ice sheet outside Antarctica. With a population of about 56,480 (2013), it is the least densely populated territory in the world. About a third of the population live in Nuuk, the capital and largest city. The Arctic Umiaq Line ferry acts as a lifeline for western Greenland, connecting the various cities and settlements. Greenland has been inhabited off and on for at least the last 4,500 years by Arctic peoples whose forebears migrated there from what is now Canada.
Capital city of Australia are Adelaide; Brisbane; Hobart; Melbourne; Perth; and Sydney. In Australia, the term "capital cities" is regularly used to refer to the aforementioned state capitals plus the federal capital Canberra and Darwin, the capital of the Northern Territory. Abu Dhabi is the capital city of the Emirate of Abu Dhabi and the United Arab Emirates overall. In unitary states which consist of multiple constituent nations, such as the United Kingdom or the Kingdom of Denmark, each will usually have its own capital city. Unlike in federations, there is usually not a separate national capital, but rather the capital city