Kea Pass

There are three options when crossing Kea Pass. All involve following the West Mathias River to the confluence with the side creek draining Mt Carl.
Direct route
The most direct route is also the most unattractive, because of a short but extremely loose and active section of rock immediately below the grassy shelf at 1460m, south of Kea Pass.
Continue up the West Mathias River from the confluence with the side creek draining Mt Carl. This section is steep and bouldery but travel is good. Follow the creek directly to Kea Pass (do not follow the branch that flows from the west) until a small rock slab and waterfall are reached. From here, climb the short section of extremely loose, steep rock on the left to the shelf below the pass. This step has turned parties back. From the shelf the pass is straightforward.
Via stream draining Pt 1803m
Follow the West Mathias to forks at the 1300-metre contour, close under Mathias Pass, and continue up the true right branch. At J34 537864 / BW18 437 247 head south up a steep gravelly tussock slab, on to a rib that becomes broad and easy. Cross the stream draining Pt 1803m on steep gravel and use the bench on the true left to reach Kea Pass.
Early season route
An early season alternative involves heading part way up the side creek draining Mt Carl and sidling across steep slopes to join the basin immediately east of Kea Pass. When not snowcovered this is a difficult sidle on steep loose rock.
Western aspect
From Kea Pass, sidle Button Peak, descend into Harcourt Creek and then climb a steep rocky gut to reach a small plateau east of Pt 1644m. From here, sidle and descend to the north-east and to Frew Saddle.
The geological survey party reached the pass in about 1908, but did not cross ; W B Cullens, A R Cant (first crossing), April 1935