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Iron Lake, Kahurangi National Park

Image of the May 2021 Wilderness Magazine Cover Read more from the
May 2021 Issue

The Cobb Valley is a well-known jewel in the tramping crown of Golden Bay. While the popular main valley can draw flocks of trampers in summer, a lesser-known sidetrack from the Cobb Dam leads to a cluster of tranquil alpine lakes perfect for camping. By Heather Jenke

After the long, torturous drive up the Cobb Valley, the first 1.5km of the track to Sylvester Hut, provides a gentle warm-up, meandering above the shoreline of Cobb Reservoir.

The trail crosses Galena Creek, the only waterway on the route, and then turns north for the long relentless haul to Sylvester Hut.

Originally constructed around 1950, the bulldozed road provided access to the dam at Lake Sylvester which was supposed to ensure a constant supply of water to the Cobb hydro scheme. Little Sylvester Lake and Iron Lake were connected to Lake Sylvester, allowing all three lakes to drain into the Cobb Reservoir when a top-up was needed for the hydro scheme. A power line was even strung up to the Sylvester camp from the Cobb Dam. This venture was abandoned after 13 years, but its legacy remains etched into the hillside.

Steadily climbing 300m through beech forest there are only occasional glimpses of the surrounding hills to tease the eyes and imagination. Above 1200m, the landscape begins to resemble Australia: an orange, rocky road snakes between patches of tea tree, scrub and stunted beech trees. Several of these beech trees sport metal trunk-guards; these are to protect the rare parasitic native mistletoe growing on the branches from becoming a possum’s tasty dinner.

Sylvester Hut is pleasantly situated about 1km from Lake Sylvester which, in summer, is a lovely place to swim.

Continuing around the southern edge of the lake, old dams and pipework of the 1950s are still evident. Little Sylvester Lake marks the end of the official track but a well-worn trail continues up the alpine meadow to Iron Lake. Tucked into a cirque at the foot of Iron Hill (1695m), with a view of Mt Lockett and Lake Lockett to the north, the sense of wildness belies the fact that the car park is a mere 3.5hr away. There are several good locations around the lake to pitch a tent for the night.

From the lake, a cairned route leads to the summit of Iron Hill. Cresting the ridge, a breathtaking panorama unfolds; 800m directly below is the Cobb River winding its way up the valley. Stretching away, uninterrupted on all sides, lies ridge after ridge of untracked country calling out to be explored.

An alternative return route is to climb the hill to the north of Lake Sylvester and follow the faint line of the old cart track – which remains from the power scheme days – to loop around to the track near Sylvester Hut.

Total Ascent
Easy / Moderate
Car park to Sylvester Hut, 2hr; Sylvester Hut to Iron Lake, 1-1.5hr; Iron Lake to Iron Hill, 45min
Sylvester Hut ($15, 12 bunks)
Turn right off the Cobb Dam Road and across the Cobb Dam. There is a small car park at the track entrance

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Iron Hill (gpx, 9 KB)

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