Lake Rotopounamu

Rotopounamu, the greenstone lake, sits in a crater on the flank of Pihanga with no stream running in and none running out - it is fed and drained entirely through the ground, which is why the water is exceptionally clear and why the level barely moves. The walk is a loop of about five kilometres round the shore, mostly flat after a short descent from the road, through mature podocarp and beech forest that has been under sustained predator control for years. The practical result is birds: robin, tomtit, whitehead, bellbird, tui and kaka are all common enough that the loop is one of the better easy bird walks in the central North Island. There are two small beaches on the northern side where people swim in summer, and the lake is cold. The mountain above, Pihanga, is significant in the traditions explaining how the volcanoes came to stand where they do.

What you actually see

• The closed lake - no inlet, no outlet, water clear as a result.
• The loop track - five easy kilometres through old forest.
• The birdlife - robin, whitehead, kaka, the product of trapping.
• The small beaches - swimming spots on the northern shore.

When to go

October to April. Mornings are best for birdsong. The track drains well but is muddy in patches after rain.

Honest expectations

The lake is cold year round. There are no facilities at all beyond the car park. The short descent from the road has to be climbed back at the end. Sandflies near the water on still days.

Nearby

Turangi and Lake Taupo are north; Tongariro National Park is south.