Distance: 6.1 km (5.0 DOC hours) - Unmarked route, hard - Hard terrain
Altitude: 859m to 1945m. Gain: 1122m. Loss: 90m . Gradient: 11 deg (Moderate-hard)
Skills: Snow / ice (5/7) - Prolonged rivers (4/6) Winter - Iceaxe/crampons, avalanche risk (5/7)

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

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

Moderate-hard (difficulty: 4/5)
Continuous moderate climbs

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

Snow / ice (difficulty: 5/7)
Scramble with snow/ice sections, ice axe & crampons required

Prolonged rivers (difficulty: 4/6)
Frequent river travel - impassible after rain, risk of getting trapped

Iceaxe/crampons, avalanche risk (difficulty: 5/7)
Ice axe and crampons required, crosses avalanche paths

Avalanche debris can fill the canyon.

The canyon is passable at low flow, with some deep crossings. Bypass the higher waterfalls on the TL before breaking out into the tussock. The upper valley past Mathias Pass is a glacier cemetery, the ground an unstable mixture of scree, moraine, avalanche snow and melting ice remnants. In a number of places the creek is carving ice caverns under what at first appears to be scree. Care required. The upper slopes are often hard old glacier ice. A more direct line to the col is possible but the terminal face of the remnant ice field can be surprisingly steep.

Note: Described in the reverse direction to your journey

At times of high flow, avoid the canyon by climbing to 1500m on the spur to the south of the creek.