Somnus

From the bivvy at D40 297 042 in North Branch of Routeburn, which is at the head of a small avalanche path about 100m above the creek on the true left, climb the prominent ridge and rock face to gain access to the snow field above. A small couloir leading left from the head of the snow field gives access to the south ridge of Somnus.

From the bivvy at E40 303 021 climb a prominent steep couloir to gain access to the snowfields above which the south ridge can be gained.

The North Col of the Routeburn gives access over Nereus on the Rock Burn side at the lowest point. Snow, rock and a long couloir lead to the summit rocks.

The route follows the left hand of two prominent ribs that form the buttress before tending right up easier ground to finish directly on the summit. 700m of climbing mainly on solid rock with sections at up to grade 15/16, mainly on the lower buttress, before the angle eases towards the top.