Meall Aonghais and Arkle via Loch Stac

This is a long, wild hill day in far north-west Sutherland, climbing first to Meall Aonghais and then continuing along Arkle’s striking quartzite ridge above Loch Stack. At around 17 km / 10.6 miles with roughly 800 m / 2,625 ft of ascent, it fits a solid medium-grade mountain outing, but the seriousness rises quickly once you leave the approach track. The ground is often pathless, the ridge is rocky and exposed in places, and the remoteness means you should treat it as a proper Highland mountain route rather than a simple hillwalk. The usual start is the small roadside parking area on the A838 about 1.5 km / 0.9 miles north of Achfary, beside the private road and bridge at approximately grid reference NC296402. That is the nearest clear start landmark for most hikers. (walkhighlands.co.uk)

From the roadside, the first section is comparatively gentle. A private road leads in past the river and toward Loch Stack, with Arkle’s pale, broken slopes drawing the eye almost immediately. The approach to Lone and the track beyond give you time to settle into the day before the route turns rougher. Expect roughly 4 to 5 km / 2.5 to 3.1 miles of easier progress here, with only modest ascent, but do not underestimate how useful this section is for pacing, checking weather movement, and confirming that the upper ridge is clear enough for your plans. Walkhighlands describes the approach as a good track before the route leaves it for pathless ground, and notes that the mountain is usually climbed from the Achfary side. (walkhighlands.co.uk)

Climb to Meall Aonghais

After the track section, the route breaks left off the main line and heads uphill across open slopes toward Meall Aonghais. This is where the character changes. Any trace of path becomes faint and intermittent, and the climb is typically through heather, stones, and uneven mountain ground. Over about 2 to 3 km / 1.2 to 1.9 miles, you gain much of the day’s height, and the ascent can feel steeper than the map suggests because the terrain is loose in places and rhythm is often broken by small route choices. Walkhighlands notes a tiny cairn and a faint path at first, but says this soon fades, leaving a largely pathless ascent. (walkhighlands.co.uk)

Meall Aonghais itself is not just a warm-up top. At about 581 m / 1,906 ft, it is an excellent viewpoint over Loch Stack and across to the surrounding Sutherland hills. The broadening panorama begins to reveal the scale of the country: Ben Stack rising nearby, the long pale architecture of Arkle ahead, and the wider sweep toward Foinaven. If cloud is low, this is a sensible place to reassess. The onward ridge is the highlight of the route, but it is also the part where poor visibility, wet rock, or strong wind can turn a medium outing into a much more committing one. The mountain’s quartzite gives Arkle its distinctive shattered appearance, but that same rock can be slick when damp. (mapcarta.com)

The ridge to Arkle

From Meall Aonghais, the route continues toward Arkle’s south-east top and then the main summit along a narrow, curving ridge. This is the most memorable part of the day and the section that demands the most care. The ridge is airy rather than technical, but there are steep drops, rocky steps, and at least one exposed section where hands may be useful for balance. Walkhighlands describes straightforward scrambling on slippery quartzite in places, and several route accounts emphasize the narrowness and drama of the crest. (walkhighlands.co.uk)

Distance-wise, the ridge section is not especially long, but progress can be slow. Allow around 2 km / 1.2 miles from Meall Aonghais over the intermediate high ground to Arkle’s summit area, and expect to move more deliberately than on the lower slopes. In clear weather, this is one of the finest viewpoints in the region. Loch Stack lies dark below, Foinaven’s white-toned quartzite mass dominates the horizon, and the wider landscape opens toward Cranstackie, Meall Horn, and the remote interior of north-west Sutherland. The ridge is one of those places where wind exposure