From the head of the Rolleston River sidle north across the scree slopes on the true-left of the river to access the east face of Mt Armstrong. Towards the northeast corner of the face a large rock toe protrudes onto the scree and can be used as a starting point to climb up the face towards point 2010m directly above. The climb takes place on a mixture of good, solid rock and loose scree/rotten rock. Halfway up the face is a short but steep rock step that must be climbed. Once point 2010m is reached, follow the East Ridge all the way to the summit.
- Alpine (Technical) 2+
- Alpine (Commitment) II