The Cradock Channel is one of three channels connecting the

Hauraki Gulf The Hauraki Gulf / Tīkapa Moana is a coastal feature of the North Island of New Zealand. It has an area of 4000 km2,Auckland Auckland (pronounced ) ( mi, Tāmaki Makaurau) is a large metropolitan city in the North Island of New Zealand. The most populous urban area in the country and the fifth largest city in Oceania, Auckland has an urban population of about ...

, New Zealand. It is the central channel, lying between

Great Barrier Island Great Barrier Island ( mi, Aotea) lies in the outer Hauraki Gulf, New Zealand, north-east of central Auckland. With an area of it is the sixth-largest island of New Zealand and fourth-largest in the main chain. Its highest point, Mount Hobson ...

to the east and

Little Barrier Island Little Barrier Island, or Hauturu in Māori language (the official Māori title is ''Te Hauturu-o-Toi''), lies off the northeastern coast of New Zealand's North Island. Located to the north of Auckland, the island is separated from the mainla ...

to the west. The other two channels are the

Jellicoe Channel The Jellicoe Channel is one of three channels connecting the Hauraki Gulf with the Pacific Ocean to the northeast of Auckland, New Zealand. It is the westernmost channel, lying between Cape Rodney on the North Auckland Peninsula and Little Barri ...

and the

Colville Channel The Colville Channel is one of three channels connecting the Hauraki Gulf with the Pacific Ocean to the northeast of Auckland, New Zealand. It is the easternmost channel, lying between the southern end of Great Barrier Island and Cape Colville a ...

. Approximately 17,000 years ago during the Last Glacial Period when sea levels were significantly lower, the area was a part of a vast coastal plain. The area where the Cradock Channel exists was where the

Waitematā Harbour Waitematā Harbour is the main access by sea to Auckland, New Zealand. For this reason it is often referred to as Auckland Harbour, despite the fact that it is one of two harbours adjoining the city. The harbour forms the northern and easter ...

(then a river) and the

Mahurangi River The Mahurangi River in northern New Zealand flows through the town of Warkworth and into Mahurangi Harbour, which opens into the outer Hauraki Gulf. The Left Branch of the river rises in the Dome and flows through the Dome Valley, while the Right ...

passed before reaching the

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...

References

Hauraki Gulf Straits of New Zealand Great Barrier Island Landforms of the Auckland Region {{Auckland-geo-stub