Getting there
From Killin, drive north out of the village, cross the River Lochay, then turn left onto a narrow road with occasional passing places. Follow this road for 11km to its end where parking is available beside some curious cows and their feed.

Sgiath Chuill
Heading south from the car-park, cross the River Lochay via the bridge and follow the track through the felled wood to reach the hydro pipe. Follow the pipe up to the top of the track, go through a gate, then at the edge of the forest, turn left on a faint path over wet ground to a small dam. Cross the dam then continue uphill south-west over wet and heathery ground. A path appears as progress is made up the hillside, follow this to the small cairn on Meall a'Churain. Continue south over another top to the summit cairn of Sgiath Chuill, which is a fine spot to photo Ben More and Stob Binnein from.

Meall Glas
Retrace your steps north for 200m, then head off west down over steep grassy ground with occasional boulders and no path. The ground is engulfed in fairly deep heather over the wide bealach. Cross the burn, head uphill, aiming west-north-west just south of Beinn Cheathaich. A direct ascent of Beinn Cheathaich can be difficult in icy conditions, keeping to the south of the summit will avoid any of these. Reaching the ridge, a path is joined, which is followed over easy ground to the summit of Meall Glas.

Beinn nan Imirean
To include the corbett Beinn nan Imirean, a detour of around half an hour is needed. Leave Meall Glas's summit and head south-west, the ground steepens and careful route selection is needed to avoid some crags. Cross the grassy bealach and climb to the summit. To continue onto Ben Challum, aim north and drop to the top of a loose track (not marked on the Landranger map).

Ben Challum
From Meall Glas's summit, aim south-west, and drop down the steep ground avoiding some crags. Turn west, the ground becomes easier and wetter, aim for the top of a track (not marked on my 2004 OS landranger map). Follow the track until it turns north, leave the track, cross a burn and reach the River Lochay. Cross the river then strike uphill, by first crossing a track (not marked on map) then trudging over wet grassy ground. As the ground levels out, it becomes drier and a faint path is picked up. Follow this path to Ben Challum's summit with its large cairn and great views.

Cam Chreag
Aim west-north-west down the north-west arm of Ben Challum, lower down iron posts are followed and a few steep rocky bits can be slightly problematic in ice. At Bealach Ghlas Leathaid, follow the line of fences north uphill over grassy ground. As the fences turn east, leave them and aim north towards Cam Chreag's ridge. On the ridge, turn north-west and continue over some bumps to the corbett's summit.

Creag Mhor
About turn and continue for ½km and look left for the route down, there is no path, but the route is fairly obvious and easy over grass. At the bealach, aim north-east for ½km, then north, contouring around Stob nan Clach and reach the south-western arm of Creag Mhor. A path appears, follow this over grass, then boulders to Creag Mhor's summit.

Beinn Heasgarnich
From the cairn, turn west-north-west and go downhill over boulders to reach grass. Turn north, then north-east to follow a burn down to the bealach below Sron Tairbh. Slog uphill on a developing path over grassy ground. At around 950m, the ground levels out, continue east following the path. A further bit of uphill is followed by more flat ground, where the path can be difficult to follow in mist. Gravel ground indicates Beinn Heasgarnich's smallish cairn is not far away.

Return
Leave Beinn Heasgarnich and aim east downhill, then pick up a burn and follow it for 3km over heather and occasional marsh. Leave it and turn east to aim for the highest point on the hydro road. Once on the road, jog back down to your car.