Whangaroa Harbour (/ˈfæŋəroʊ.ə/; Māori pronunciation: [faŋaɾɔa]), previously spelled Wangaroa Harbour, is an inlet on the northern coast of Northland, New Zealand. Whangaroa Bay and the Pacific Ocean are to the north. The small settlements of Totara North and Saies are on the west side of the harbour, Waitaruke on the south side, and Whangaroa on the east. State Highway 10 runs through Waitaruke. The name comes from the lament "Whaingaroa" or "what a long wait" of a woman whose warrior husband had left for a foray to the south. The harbour was formed when rising sea levels drowned a river valley about 6,000 years ago. Steep outcrops remain from ancient volcanic rocks.
There are extensive mangrove swamps at the head of the harbour, and some of the oldest fossils in the North Island, dating to the early Permian about 270 million years ago, are in the Whangaroa area.
According to Māori traditions, the waka Māhuhu-ki-te-rangi explored the Whangaroa harbour during early Māori settlement of New Zealand. The area was settled by descendants of Te Māmaru and Mataatua waka crews.
Whaling and other ships visited Whangaroa from 1805 to 1809, including the General Wellesley and Commerce in 1806, and Elizabeth in 1809. Sixty-six members of the crew of the Boyd were killed by local Māori in 1809 after the crew whipped the son of a chief. The visits ceased as a result, resuming when the Dromedary loaded timber in 1819.Southern Right Whales were severely depleted by the hunts and almost disappeared from the area, while dolphins and killer whales still visit the harbor more frequently.