Tiorga Mor from Lochan Beag via Loch Leosaid

This difficult hill route on North Harris heads into a lonely, water-cut landscape of lochs, moor, steep ridges, and broad mountain shoulders, climbing roughly 10 km / 6.2 miles with about 700 m / 2,300 ft of ascent. The commonly used start is at the track for the Chliostair power station on the B887, near Amhuinnsuidhe, Isle of Harris, with the mapped start point at grid reference NB052077. That places the hike near the Lochan Beag / Loch Leosaid hydro track junction on the B887, rather than at a formal visitor trailhead. Walkhighlands notes there is no formal car park, and that walkers usually find a small roadside space near the cattle grid or a little way up the power-station road. (walkhighlands.co.uk)

Although your stated distance is around 10 km, it is worth planning for a bigger mountain day in this terrain. A widely used route to Tiorga Mòr from this side is listed at 16.25 km / 10 miles with 720 m / 2,362 ft of ascent, and the ground is described as rough, pathless in places, steep, and boggy. That means even a shorter out-and-back or more direct variation still deserves full mountain preparation, especially because route-finding can be more demanding here than the raw mileage suggests. Using HiiKER to study the line in advance is sensible, particularly for identifying the loch-side track, the boggier glen sections, and the point where the route leaves any clearer path. (walkhighlands.co.uk)

What the route feels like

The opening section is comparatively straightforward, following the power-station road and then a rougher track as the route trends toward the west side of Loch Leosaid. This early approach gives a gradual introduction to the character of the day: engineered hydro features at low level, then increasingly open moorland and mountain ground beyond. Tiorga Mòr rises ahead as a broad, serious hill rather than a sharply defined peak, and the sense of remoteness builds quickly once you leave the road behind. (walkhighlands.co.uk)

Beyond the bridge over the Abhainn Leosaid, the route becomes more committing. Walkhighlands notes that the old path up Gleann Leosaid is partly lost on flat, boggy ground, and that footbridges shown on some mapping are not there, so hikers often stay on the north side of the river until a more distinct path reappears near old ruined shielings. That is one of the key planning points for this walk: the lower glen can be wet, confusing, and slow, especially after rain. Waterproof footwear, gaiters, and conservative timing matter here. (walkhighlands.co.uk)

Higher up, the route leaves the old glen path and turns onto wetter, pathless slopes near Loch Braigh Bheagarais, then climbs toward the bealach between Ceartabhal and Tiorga Mòr. The final ridge steepens at first, with crags that are generally avoidable, before easing onto a narrower upper crest with traces of path. The summit itself is marked by a trig point and has a dramatic position above the west coast of Harris. On a clear day, views extend over sea lochs, offshore islands, and the broken Atlantic-facing coastline. (walkhighlands.co.uk)

Terrain, hazards, and navigation

This is not a casual hillwalk. The main difficulties are not technical scrambling so much as bog, steep grass, broken rocky ground, and intermittent or absent paths. The lower glen can be saturated, the mid-mountain slopes can be tiring underfoot, and the descent options on the broader northern side require care because there are cliffs and broken crags in places, especially toward the Sròn Uladal side. (walkhighlands.co.uk)

Strong wind, low cloud, and rain can transform the outing. Tiorga Mòr stands at 679 m / 2,228 ft, high enough to catch poor visibility and harsher weather than the coast below. In mist, the broad upper ground and multiple lochans can make bearings awkward, so this is a route where preloaded mapping on HiiKER is especially useful. Expect slower progress than the distance alone suggests