Climb to the top of the Welchman Glacier, then climb the obvious wide, steep couloir (55 to 60 degrees) to Bernard Col, 400m north-east of the summit of Mt Burns.
A couple of alternatives may be possible if the couloir can’t be used due to bergschrund and/or cornice conditions:
climb mixed ground 250m to the right of the wide couloir, or
traverse from the true left edge of the upper Welchman Glacier across to the Main Divide.
The descent to the McKerrow Glacier used to be straightforward (grade II, 1+), descending snow slopes to the north-north-west into a gully that reaches the glacier at around BY15 570 533. The lower part of the route has become complicated by rock bluffs and over-steepened gravel slopes due to glacial recession. It’s not recommended as a crossing route.
If crossing from the west, three abseils are usually needed to get form the Divide to the Welchman Glacier.
