Australia, island continent located southeast of Asia and forming, with the nearby island of Tasmania, the Commonwealth of Australia, a self-governing member of the Commonwealth of Nations. The continent is bounded on the north by the Timor Sea, the Arafura Sea, and the Torres Strait; on the east by the Coral Sea and the Tasman Sea; on the south by the Bass Strait and the Indian Ocean; and on the west by the Indian Ocean. The commonwealth extends about 4,000 km (about 2,500 mi) from east to west and about 3,700 km (about 2,300 mi) from north to south. The area of the commonwealth is 7,682,300 sq km (2,966,200 sq mi), and the area of the continent alone is 7,614,500 sq km (2,939,974 sq mi), making Australia the smallest continent in the world, but the sixth largest country. The capital of Australia is Canberra, and the largest city is Sydney; both are located in the southeast