Mount Harper / Mahaanui is a mountain in Canterbury, New Zealand, within the foothills of the Southern Alps / Kā Tiritiri o te Moana. The mountain is the tallest point of the Harper Range, which is separated from the nearby Ben Macleod and Tara Haoa ranges to the south by the Rangitata River, and from the Moorhouse Range to the east by the Pudding valley. A number of small lakes lie to the north of Mahaanui, most notably including Lake Clearwater.