NG5603521623 From the car park return to the road and join the well-used trail on the north side of the Allt na Dunaiche. Landowners the John Muir Trust have done a good job with the path here, which is well made and easy going. Follow it west, above the cascading Allt na Dunaiche in its deep wooded gorge. The woods soon thin out and the path climbs open ground to meet the Allt na Dunaiche in the wide bowl of Coire a' Caise. From here the gully-seamed cliffs of Bla Bheinn and Clach Glas look immense.

NG5451921647 Cross the main burn and continue west, before hopping over the burn that drains Coire Uaigneach. The path now gets stuck into the steeper ascent up the sloping floor of Coire Uaigneach. At first you get stone steps, but soon the path surface deteriorates and there's some rough, loose going. This initial ascent eases off into a grassy bowl at about 400m.

NG5360221232 The continuation above doesn't look that appealing, and to be frank it's not. At this stage the path peters into several possible trails. Bear briefly left and then cut back up right to skirt the initial broken crags, then follow your nose up steep ground. The obvious way is a steep scree gully, while if you avoid this then there are some limited opportunities for scrambling. If there are other parties on the slope then loose rocks are potentially a bit of a hazard. Bear slightly right in ascent, to reach the crest of Bla Bheinn's east spur. This gives a rocky ascent, with spectacular views out over the cliff edge. Look out for the Great Prow, a huge fin that projects from the cliffs (home to some challenging mountain rock climbs). Higher up is an excellent viewpoint on the neighbouring rock peak of Clach Glas (worth trying to pick out the intricate descent route from its summit, for a future Clach Glas-Bla Bheinn traverse). Towards the top of the spur there's a brief scramble in a shallow gully; easier ground then leads to the summit trig point.

NG5298221743 Thanks to its isolated position Bla Bheinn's views are incredible, with the jagged skyline of the main Cuillin ridge arrayed to the west. A descent of the south ridge comes highly recommended, but leaves you a long way from the start. The logistically straightforward option is just to go back the way you came - and the views in descent make up for re-treading all that loose ground.