West Auckland is one of the major geographical areas of Auckland, the largest city in New Zealand. Much of the area is dominated by the Waitākere Ranges, the eastern slopes of the Miocene era Waitākere volcano which was upraised from the ocean floor, and now one of the largest regional parks in New Zealand. The metropolitan area of West Auckland developed between the Waitākere Ranges to the west and the upper reaches of the Waitematā Harbour to the east. It covers areas such as Glen Eden, Henderson, Massey and New Lynn.

The Whau River is an estuarial arm of the southwestern Waitemata Harbour within the Auckland metropolitan area in New Zealand. It flows north for 5.7 kilometres (3.5 mi) from its origin at the confluence of the Avondale Stream and Whau Stream to its mouth between the Te Atatū Peninsula and the long, thin Rosebank Peninsula in Avondale. It is 800 metres (2,600 ft) at its widest and 400 metres (1,300 ft) wide at its mouth.