Australia, officially the Commonwealth of Australia, is a sovereign country comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands. It is the largest country in Oceania and the world's sixth-largest country by total area. The population of 26 million is highly urbanised and heavily concentrated on the eastern seaboard.

California, officially the State of California, is a state in the western part of the United States. It is the third largest state by total area and the largest by population in the United States. Its largest cities are Los Angeles, San Diego, San Jose, and San Francisco. The capital is Sacramento. It is bordered by Arizona to the southeast, Oregon to the north, Nevada to the east and the Mexican state of Baja California to the south.