The Whakapapa River in New Zealand forms from streams which trickle off the Whakapapa skifield of Mount Ruapehu and down the western slopes of the mountain. The river passes near Ōwhango, before finally merging with the Whanganui River just east of Kakahi, about 40 km (25 mi) from where it starts, which is in a 100 m (330 ft) deep gorge, at the confluence of the Whakapapaiti and Whakapapanui Streams.