Distance: 3.8 km (4.0 DOC hours) - Unmarked route, hard - Hard terrain
Altitude: 480m to 1325m. Gain: 1264m. Loss: 420m . Gradient: 28 deg (Steep)
Skills: Alpine weather (2/7) - Streams (2/6)

Unmarked route, hard (8/9)
Unmarked route, no clear geographic features to follow

minor (5/5)
A viable route, not widely used

Steep (difficulty: 5/5)
Steep climbs of >1000m

Hard (difficulty: 5/5)
Thick scrub-bash / continuous river boulders, waterfalls, or gorges

Alpine weather (difficulty: 2/7)
Tramp on open tops, exposed to alpine weather

Streams (difficulty: 2/6)
Small streams, danger only in extreme weather

Unknown (difficulty: 0/7)
Not specified

This route took me 4 hours heading up from Harris Creek in January 2025.

Crossing the stream near the picnic table, find the foot of the spur, it dawdles until the spur becomes obvious, the travel is nice and open through here with thick green ground covering.

You will see a few tape marker and be able to follow an old cut through the bush, as you gain elevation the scrub and leatherwood becomes thick and is over head height.

You can squeeze under some and push through others. It sucks.

The scrub line starts around 750m elevation with the thickest leatherwood between 800 - 1100m elevation.

The terrain opens a little past 1100m and you start to get some views, once you reach 1300m the travel is easy and you are nearly at West Peak

Note: Described in the reverse direction to your journey

Taken from Paul McCredie TTC trip report
https://www.ttc.org.nz/pmwiki/pmwiki.php/TripReports/2021-01-08-TriangleSpur-MtDundas

Down the NW spur to the Harris Creek- Mangahao confluence. The upper part of the spur is good going, but this spur has a long scrub belt. The first part of the scrub belt before pt 1090 had a surprisingly good footpad, heavily used by deer, to judge by the many prints.
Further down the scrub was quite a bit thicker in places though the footpad was still mostly visible and many old cut branches showed people have used it, though there were no other markers.

The travel improved after reaching the bush, past pt 832. The GPS is useful to help stay on the right spur.

It took three hours from West Peak down to the Mangahao.
If Harris Creek Hut still existed, and the route was cleared through the scrub, this would be a great way to approach Dundas Hut.

In 2025 the scrub was so horrible on the way up that I opted to bush bash down a different spur and then down climb a large slip to avoid leatherwood.