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Baby Sister

A scrappy line in Castle Ravine

Ski Touring Difficult

548 m
0 m
301 m
0-1 hrs
Low Point
1.2 km
High Point
1.5 km
Baby Sister Map

Baby Sister is the most striking line in Castle Ravine in the summer, with the largest rock buttress forming it's right boundary. This leads many to wonder, "is that a ski line in the winter?" The answer is yes, but unfortunately it almost never receives enough snow deposit from the wind to make it worthwhile or even skiable. The boulders and scree are quite large and tend to create too much of an obstacle for it to ski very well. That being said, it's there if you want it. If you like adventure this may be for you, if not, stick to the South-North Sisters if you’re going to put in the effort to ski Castle. The line drops off a little skiers left of Edmunds Col, it can be tricky to spot from above, but once you locate the prominent rock buttress to skiers left, you can pick you way down the snow/scree field until it's possible to join the runout of the Sisters.



Serious gradient of 30-38 degrees where a real risk of slipping exists.

Medium Exposure (E2)

2 out of 4

As well as the slope itself, there are some obstacles (such as rock outcrops) which could aggravate injury.


4 out of 4

In the high mountains or remote conditions, all individuals must be completely autonomous in every situation.

Best time to visit

between March and April


  • Face
  • Alpine
  • Cliffs
  • Single Descent
  • Ski Mountaineering

Equipment required

  • Skins
  • Ice axe
  • Crampons