sydneySydney is known as the Harbour City. It's the largest, most populated, oldest and most cosmopolitan city in Australia with an enviable reputation as one of the world's mostSydney is the capital city of the state of New South Wales and the most populous city in Australia. Located on Australia's east coast, the metropolis surrounds Sydney Harbour and extends about 80 km (50 mi) from the Pacific Ocean in the east to the Blue Mountains in the west, and about 80 km (50 mi) from Ku See more