Properly speaking, the Hauraki Gulf is the body of water limited to the south by the Inner Islands (from Rangitoto to Waiheke), and in the north and east by Little Barrier Island, Great Barrier Island and Cape Colville. But in this section it is more logical to consider the whole marine unit that includes, beside the Gulf, the Firth of Thames, the Waitemata Harbour, the Tamaki Straits, and the islands north of the Barriers (Hen and Chickens, Mokohinau, Poor Knights), and east of Cape Colville (Cuvier, Mercury).

(This page is under re-construction)