Western Australia is a state of Australia, occupying the entire western third of the Australian continent. It is bordered by the Indian Ocean to the north and west, the Great Australian Bight and Indian Ocean to the south, the Northern Territory to the north-east and South Australia to the south-east.

Western Australia is Australia's largest state and the second largest subnational entity in the world. It has 2.2 million inhabitants (10% of the national total), 85% of whom live in the south-west corner of the state.

The southwest coastal area has a Mediterranean climate and was originally heavily forested, including large stands of the karri, one of the tallest trees in the world.