The hike starts with a boat trip from the town to the other side of the lake to reach the trailhead. Pretty much everyone on the boat is heading for the trail as that is one of the only stops the boat makes. It's a chance to meet fellow hikers (or size up the competition). From the landing dock the trail begins a switch-back climbing steeply away from the lake and into a huge valley. There is not much shelter once you leave the forest so good head gear and sun cream is a must. You pass two giant waterfalls as you climb higher in the valley, with increasingly stunning vistas.

At the top of the valley you reach the most famous section of the hike: a steel ladder that leads to a tunnel through which you have to scramble. On the other side is a chain to assist you on the climb up a cliff edge with a sharp drop. Once you reach the high ground you've climbed around 700 metres from the jetty. Things level out here and after a short walk through more trees you finally reach the lake itself: a stunning pool of turqoise water framed by steep ridges and a number of good spots to take in the view. There is some ice on the lake's surface all year round. We couldn't resist a plunge into the water, but it was a quick one given the icy temperature of the water.