Waikato River

The Waikato River is the longest river in New Zealand, running for 425 kilometres through the North Island. It rises in the eastern slopes of Mount Ruapehu, joining the Tongariro River system and emptying into Lake Taupo, New Zealand's largest lake. It drains Taupo at the lake's northeastern edge, creates the Huka Falls, and then flows northwest, through the Waikato Plains. It empties into the Tasman Sea south of Auckland, at Port Waikato. It gives its name to the Waikato Region that surrounds the Waikato Plains. The present course of the river was largely formed by the large volcanic eruption from the Lake Taupo volcanic complex 1800 years ago. The large outflow of volcanic debris blocked the old channel to the Firth of Thames at Lake Karapiro and forced the river to turn west and then north. The remains of the old river path can be clearly seen at Hinuera where the cliffs mark the ancient river edges. The river's main tributary is the Waipa River, which has its confluence with the Waikato at Ngaruawahia.

The name Waikato comes from the Māori language and translates as flowing water.

The Waikato River has spiritual meaning for various local Māori tribes, including the large Tainui, who regard it as a source of their mana, or pride. The widely-respected marae of Turangawaewae is close to its banks at Ngaruawahia.

For many years Tainui tribe have sought to re-establish their links to the river after the New Zealand Wars (see Invasion of Waikato) and the subsequent confiscations of the 1860s, and are continuing negotiations with the New Zealand government. The Tainui iwi was advised not to bring a case for the river before the Waitangi Tribunal as they would not win. An out of court settlement was arranged and the deed of settlement signed by the Crown and Waikato-Tainui in August 2008 settled the raupatu claim to the Waikato River, although other claims for land blocks and harbours are still outstanding. Waikato-Tainui now have joint management of the river with Environment Waikato.