Which Is the Largest Natural Harbor in the World?

Over 11 miles long and covering an area 21 square miles in size, Sydney Harbour, in Sydney, Australia, is also called Port Jackson. The harbor is home to several islands, many of historical significance. It also houses a large variety of fish — totaling over 580 species. The harbor's large volume, approximately 500 gigalitres, is the base of the Sydharb, an official Australian unit of volume.