At 1686m, Ohuinga is Ruahine Forest Park’s ninth-highest peak. It marks the point where the Ruahine and Hikurangi ranges connect and its name acknowledges that it is also the meeting point between Te Hekenga and Rangi-o-te-Atua.   

The most direct route to Ohuinga begins on the east side of the range at Mill Road end (480m). After following a farm track and the Tukituki River, ascend Rosvalls Track to Pt1285, then turn north on the route up to Tarn Bivvy. From there it’s another 3km or so and nearly 400m of ascent up Black Ridge. The ridge route is broad and gentle and passes tarns before reaching a saddle, followed by a 200m scramble on scree and snowgrass to the summit. Allow about five hours to the hut and another two or three to the summit. From Ohuinga the views northwest to the Hikurangi Range and south over Sawtooth Ridge to Tiraha are ample reward for the climb. 

Rather than retracing your steps down Black Ridge, a more satisfying option is to cross the craggy and sometimes knife-edged Sawtooth Ridge, between Ohuinga and Tiraha. Sawtooth Ridge has a formidable reputation which is deserved in winter or bad weather conditions, but in calm and clear conditions it’s an absorbing 1–2hr traverse requiring some scrambling but nothing technical. Tiraha’s summit is reachable in one 8–10hr day from Mill Road and there is a great bivvy spot near a tarn at 1600m, just west of the summit. 

If time allows, a better option is to descend Daphne Ridge to Howletts Hut – 300m below and 2km south of Tiraha. From there, follow Daphne Spur to Daphne Hut then ascend the lower section of Black Ridge to rejoin Rosvalls Track at Pt1285. 

While this route requires nearly 700m of ascent from Daphne Hut, it allows you to complete a full circuit.

In fine summer conditions, with the option to bivvy just west of Tiraha it’s possible to complete this circuit in two 8–10hr days. A less demanding approach, though, is to spend a first night at Tarn Bivouac (4–5hr), then cross the tops and descend to Howletts Hut (4–6hr) for a second night and walk out on day three (6–8hr).