The Waiapu River is a 90-kilometre long river of the East Coast of the North Island

North Island

The North Island is one of the two main islands of New Zealand, separated from the much less populous South Island by Cook Strait. The island is in area, making it the world's 14th-largest island...

 of New Zealand

New Zealand

New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

. Flowing from the Raukumara Range

Raukumara Range

The Raukumara Range lies north of Gisborne, near East Cape in New Zealand's North Island. It forms part of the North Island's main mountain chain, which runs north-northeast from Wellington to East Cape, and is composed primarily of greywacke, argillites, siltstones and sandstones. The North...

, it passes through Ruatoria

Ruatoria

The town of Ruatoria is located in the East Coast region of New Zealand's North Island. It is the second largest centre of population in the sparsely populated region, yet has a population of only 900 .- Geography :...

 before reaching the Pacific Ocean

Pacific Ocean

The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...

 at Rangitukia

Rangitukia

Rangitukia is a small settlement 10 kilometres south of East Cape in the northeast of New Zealand's North Island. It is located close to the mouth of the Waiapu River....

. The river lies within the rohe

Rohe

Rohe is a word used by the Māori of New Zealand to describe the territory or boundaries of tribal groups. In traditional times, rohe were defined according to prominent geographical features, including mountains, rivers, and lakes. This is generally the case today as well....

 of the Ngati Porou

Ngati Porou

Ngāti Porou is a Māori iwi traditionally located in the East Cape and Gisborne regions of the North Island of New Zealand. Ngāti Porou has the second-largest affiliation of any iwi in New Zealand, with 71,910 registered members in 2006...

 iwi

Iwi

In New Zealand society, iwi form the largest everyday social units in Māori culture. The word iwi means "'peoples' or 'nations'. In "the work of European writers which treat iwi and hapū as parts of a hierarchical structure", it has been used to mean "tribe" , or confederation of tribes,...

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The river was the site of hostilities between July and October 1865 during the New Zealand Wars

The river has two branches, the Tapuaeroa River

Tapuaeroa River

The Tapuaeroa River is a river of the Gisborne Region of New Zealand's North Island. It flows southeast from its sources in the Raukumara Range, joining its waters with those of the Mata River close to the town of Ruatoria, the resulting flow becoming the Waiapu River....

 and the Mata River

Mata River

The Mata River is a river of the East Coast of the North Island of New Zealand. It flows northeast from the slopes of Mount Arowhana in the Raukumara Range to join with the Tapuaeroa River close to the settlement of Ruatoria, in doing so forming the Waiapu River, which reaches the Pacific Ocean...

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