Stob Bàn's north eastern face is precipitous and craggy and drops steeply to the valley of the Allt na Lairige. All drainage from the mountain finds its way to Loch Treig to reach the sea via the River Spean and Loch Linnhe at the west coast. One unusual characteristic of Stob Bàn is the so-called Giants Staircase, this is a 200-metre stretch of quartzite slabs encountered when descending from the 800 metre col between Stob Bàn and Stob Choire Claurigh to the Lairig Leacach, the staircase is awkward to negotiate especially in wet conditions.