NN0801026749 From the layby walk up steps signed for the Falls of Cruachan railway halt. Duck beneath the railway via a low underpass, then take the path uphill into dense birch woods. A steep and often muddy climb through the trees above the east bank of the Allt Cruachan brings you to a collapsing stile over a deer fence, and open ground. Continue beside the burn, pass under a pylon line, then follow a tarmac access road up to the impressive Cruachan dam, which feeds a pumped storage hydro scheme buried deep in the mountain.

NN0796728136 At the foot of the dam go left up steps, then climb a metal staircase onto the top of the dam itself. From the west end of the dam bear right on a rough path, then join the track along the west shore of the Cruachan Reservoir. Many people bypass the first peak of the horseshoe, Meall Cuanail, but it's well worth including. To climb it leave the track at a concrete water outlet, and head west up steep grassy slopes leading to Meall Cuanail's broad south spur. This gives a long ascent to the summit cairn. [The non-summit alternative is to continue on the reservoir road for a further 1km, then turn left to follow the well-trodden path up Coire Dearg to the col just north of Meall Cuanail]

NN0696129557 Descend a rocky path north to the bealach at the head of Coire Dearg. Pass a little pool and join the eroded trail for the steep climb up Ben Cruachan's rocky south ridge. By erring slightly to the right of the path it's possible to contrive some limited scrambling; on the other hand, in winter conditions it's safer to stay comfortably left of the steep edge overlooking Coire Dearg. With its great height above the surrounding hills the summit of Ben Cruachan is a stunning viewpoint; dozens of summits can be seen, from the Paps of Jura to Ben Nevis.

NN0695530475 Heading down the east ridge, a brief burst of easy scrambling on blocky granite leads to easier, though still rocky, ground. In winter conditions the scrambling step needs great care. Descend along the edge of the Coire Caorach cliffs, giving a wide berth to any cornices, to reach a little notch. Scramble up out of this on sound slabby rock, or bypass the scramble to the right, then continue along the rocky crest over a rough minor summit (spot height 950m), before climbing steadily onto Drochaid Ghlas. This summit stands slightly north of the main ridge, and though it can be bypassed its airy peak is worth a one-minute detour.

NN0831030753 A steep descent south and then east leads on down the ridge to a col. From here it's a steady plod up to the cone of Stob Diamh. At the summit cairn turn right, following the south ridge around the rim of an impressive deep corrie. Beyond a little dip is a last climb to the day's final summit, Stob Garbh. Continue roughly south-southeast, then bear slightly right to pick up the broad south ridge of the hill, leading down to the deep saddle of the Lairig Torran below the outlying Corbett of Beinn a'Bhuiridh (an optional extra not described here).

NN0947828925 Bear west, descending boggy open ground. The path is easily misplaced, but as height is lost it becomes more distinct. Cross a burn and traverse southwest above the Cruachan Reservoir, to reach a reservoir access road. This leads over a short rise to the east end of the dam, then continues downhill to a road junction some way below the dam. Here re-join the approach path by the Allt Cruachan.