Mokoia Island is located in Lake Rotorua in New Zealand. It has an area of 1.35 square kilometres. The island is a rhyolite lava dome, rising to 180 metres above the lake surface. It was formed after the Rotorua caldera collapsed and rhyolitic magma was pushed through the cracks. One of the cracks was below where Mokoia island is today. The foreshores of the island have geothermal springs with hot spring water forming the Hinemoa pool, known to locals as Waikimihia. It also has very rich volcanic soil, which was why the local Māori grew kumara on it. it was also a very good strategic location, which was why it was often fought over.
Mokoia Island is privately owned by local Māori iwi, who run it in conjunction with the New Zealand Department of Conservation. It is a bird sanctuary and access is limited to tour parties only. It is home to several rare species, including the North Island kōkako, the North Island brown kiwi, and a breeding population of the endangered North Island saddleback.
The island is also the location of regular Mau rākau training camps in the Maori martial art of taiaha.