Port Jackson is the natural harbour of Sydney, Australia, also known as Sydney Harbour and is the largest natural harbour in the world. Its best known features are the Sydney Opera House and Sydney Harbour Bridge.

The harbour's discovery by Europeans is credited to Lt. James Cook in 1770, although he did not enter it. Cook named the harbour after Sir George Jackson, Judge Advocate of the Fleet at the time. Cook noted "there appears to be a good anchorage" in his log. Captain Arthur Phillip established the first colony in Australia at Sydney Cove inside Port Jackson in 1788. That colony grew to become Sydney.

Geologically, Port Jackson is a drowned river valley. It is 19 km long with an area of 55 sq km. It is one of three arms extending from the single entrance. North Harbour is the shortest, and is really just a large bay extending to Manly. Middle Harbour extends to the north-west. It is bridged at The Spit and Roseville . Its headwaters lie in Garigal National Park. The longest arm, officially known as Port Jackson, extends west as far as Balmain, where it is fed by the estuaries of the Parramatta and Lane Cove rivers. Port Jackson is bridged by the Sydney Harbour Bridge. It is heavily embayed. The bays on the south side tend to be wide and rounded, whereas those on the north side are generally narrow inlets. Sydney's central business district is located on Sydney Cove, a small bay on the south side. There are four extant islands within the harbour. Several other islands have been linked to the shore by land reclamation.

The land around Port Jackson was occupied at the time of European discovery and colonization by various tribes including the Gadigal , Eora and Wanegal peoples. The Gadigal people are said to have occupied the land stretching along the south side of Port Jackson from what is now South Head, in an arc west through to Petersham . The area along the southern banks of the Parramatta River, west of Petersham to Rose Hill , was reported to belong to the Wanegal. The Eora people lived on the northern side of the harbour.

External link

• Gadigal Information Service