The Wharekōpae River is located in the northeast of New Zealand's North Island. A tributary of the Waikohu River (which is itself a tributary of the Waipaoa River), it rises on the slopes of Maungatapere, a 1,050-metre (3,440 ft) peak at the northeastern end of the Huiarau Range, and flows east, reaching the Waikohu River at the settlement of Waikohu, west of Te Karaka.^[1]

At Rere, it cascades over the Rere Rock Slide, a smooth, natural rock formation 60 metres (200 ft) long, and the picturesque Rere Falls.

The river's name is Māori for "house with a side door", which would have been an unusual feature of a traditional Māori dwelling.^[2]