The Karetu River is located in the Northland Region of New Zealand, approximately north of WhangÃÂrei. Its source is on the north-western slopes of the hill Te Rangi in the Russell Forest.
The river begins as two streams, Whakatane Stream and Karetu Stream, which join and flow down the Whaakaurau Valley through the settlement of Karetu. From here it becomes the Karetu River, and joins the Kawakawa River shortly before reaching the Bay of Islands.