04/08/2026
South Wairarapa Tramping Club trip. Rangitūmau, Sunday 12 July (With 3 MTC members and 1 WWF member researching for the Wairarapa Walking Festival). Report from John R.
Dawn brought a day of crystalline clarity after a week of bitter cold and rain. A small convoy—with its origin in Akatarawa and pickups in Greytown, Carterton, Masterton and Double Bridges—proceeded up the valley towards the peak that dominates it.
A short drive from the Lake Mallard gateway brought us to a large woolshed. On foot, we then followed the vehicle track that leads to the microwave and radio communications tower at the summit of Rangitūmau.
As we climbed, our view of the valley below expanded, as did that of the snow-capped Three Kings, rising above cloud that almost hid Pukeamoamo / Mitre.
Rangitūmau seemed to keep receding, and with it the coordinator’s hopes of an early morning tea. But at last we reached the survey mark, 604 metres above the sea.
There Peter said this karakia:
Whakataka te hau ki te uru
Whakataka te hau ki te tonga
Kia mākinakina ki uta
Kia mātaratara ki tai
E hì ake ana te atakura
He tio, he huka, he hau hu
Tìhei mauri ora
Cease the winds from the west
Cease the winds from the south
Let the breeze blow over the Iand
Let the breeze blow over the ocean
Let the red-tipped dawn come with a sharpened air.
A touch of frost, a promise of a glorious day.
Peter and John then recounted the story of Haunui-a-Nanaia, who long ago came this way after pursuing his runaway wife Wairaka down the west coast of Te Ika a Māui.
From the top of Remutaka, Hau saw a lone mountain at the northern end of the valley, which he used as a landmark. He named it Rangitūmau, meaning that it holds up the sky.
Wairarapa Māori express their identity and kinship with the land by saying, ‘Ko Rangitūmau te maunga, ko Ruamahanga te awa, ko Wairarapa te roto’ (‘Rangitūmau the mountain, Ruamahanga the river, Wairarapa the lake’). The saying recognises the mountain at the head of their valley, the great river that drains their valley and the lake at its foot.
Several trampers asked about the origin of the limestone on Rangitūmau, which is weathered into intricate shapes.
The Rangitūmau limestone consists of quintillions of broken bits of shells. Shelly invertebrates living in such numbers need clear water, free of sediment that clogs their delicate filter feeding organs. Also, the water must be less than a few hundred metres deep to allow sunlight to pe*****te, so that diatoms—the start of marine food chains—can live. However, most such sea floor is near land, where sand and mud abound.
The shelly animals that make the Rangitūmau limestone lived on a ridge free of land-derived sediment, shallow enough for light to reach it, and surrounded by deeper water where sand and mud accumulated.
This ridge was one of several caused by the pushing together of the Indo-Australian and Pacific plates, about a million years ago. It slowly rose above the water to become part of the land. Limestone of the same kind and with the same origin is found right along the eastern side of the Wairarapa valley and as far north as Hawke Bay.
Looking north from Rangitūmau we saw Mt Ruapehu looming in the distance (185 kilometres away), reminding us that we’re on an active plate boundary.
Our hosts, Viv and Chris Bunny came up on mountain bikes and stopped to chat with us in the sunshine, then executed flawless hill starts.
We were 11: Peter A, Margaret B, Sandra B, Sheila B, Chris C, Liz C, Stuart H, Katrina M, Cushla M, John R and John W.
