Rotomairewhenua/Blue Lake Track

Rotomairewhenua/Blue Lake Track is a remote out-and-back from the West Branch Sabine swing bridge to Blue Lake Hut; the lake shore is a short walk beyond the hut. The official route figure is 7.7 km (4.8 mi) each way, about 15.4 km (9.6 mi) return, and the side trip takes about seven hours of walking. A mapped line measures roughly 7 km each way, so published distances vary; the total here follows the official figure. This is not a day walk from St Arnaud: plan at least four days return from there. The shorter approach is a water taxi from Lake Rotoroa Jetty to Sabine Hut, then about five hours on foot to West Sabine Hut before this trip starts. Plan it as part of a multiday tramp and book Blue Lake Hut if you intend to stay; it has 16 bunks and requires reservations.

From the swing bridge, head upstream. For about the first 90 minutes, the track follows the Sabine valley. The valley opens out and the route passes through forest destroyed by an avalanche in 1980, a stark reminder of the terrain. Then it climbs steeply in two stages into a high basin. Expect a backcountry mix of bush, tussock, rock, scree and stream crossings, with a sustained climb rather than a smooth, groomed path. Follow the Blue Lake direction at the bridge junction instead of drifting onto the route toward Travers Saddle. DOC classifies the surrounding tramping circuit as advanced.

Blue Lake Hut sits at 1,190 m, close to the shore. Rotomairewhenua means “land of peaceful waters”; the lake is sacred to Ngāti Apa ki te Rā Tō and was traditionally used in cleansing ceremonies. Its famous clarity comes from water filtered through landslide debris on its way from Lake Constance. Take time to look from the shore: the clear blue-green water, beech forest and steep peaks make the high basin feel very different from the river valley below. Keep the lake pristine: do not touch, swim, wash, take water from it or put equipment in the water. DOC permits swimming and filling bottles in the Sabine River below the outlet instead. For a photo, frame the transparent shallows with forest and the mountain slopes behind them, from dry ground.

This is a remote alpine tramp with marked avalanche paths. Do not stop between avalanche signs, and check DOC’s current avalanche and track advice before setting out. Freezing conditions can occur year round, and heavy rain can make stream crossings unsafe. There is no road access to the swing bridge and no parking there; the route starts on foot from West Sabine Hut. The Blue Lake Hut stay requires a booking and seasonal fees apply. No food service was found along this route, so carry what you need for the approach and overnight stay. Dogs are not allowed.