Heading up the Zig-Zags on Bidean nam Bian

Bidean nam Bian via the Zig-Zags

Rock-scrambling route up Bidean nam Bian via Gearr Aonach

A super summer rock-scrambling route up Bidean nam Bian, heading up via Gearr Aonach and Stob Coire nan Lochan. There are a couple of exposed Grade 1 (bordering on Grade 2) rock-scrambling pitches on the Zig-Zags part of this route where some people may find the use of a rope reassuring.

Route outline

  Map base ©OpenStreetMap
Munros Bidean nam Bian
Stob Coire Sgreamhach
Ascent 1325m (4340ft)
Distance 10km (6m)
Time 5:00hr
Start/finish Three Sister's car-park
Grid Ref : NN171569
easy hard
easy hard
easy hard
ok fab

Being such a complex mountain, there are lots of routes to choose from to explore Bidean nam Bian. The Three Sisters look impenetrable from Glencoe, but there is a fine summer scrambling route that climbs the central buttress and is much easier than expected. This route is often referred to the 'Zig Zags of Gearr Aonach' - it twists and turns as it climbs up the rock.

The Zig Zags of Gearr Aonach route is generally classed a Grade 1 scramble, though a couple of short sections are fairly exposed and bordering on Grade 2, where some people may prefer the security of a rope. For the most part being on a fairly well trodden path, route finding is pretty straightforward, but be aware there are some sections of paths that initially look like they are by-passing awkward moves - they're actually dead-ends !

Route detail

Getting to the start in Glencoe »
  • Start from one of the large car-parks on the south-side of the A82 in the heart of Glencoe, just west of the 'Pass of Glencoe'. The start point is the same as the finish point.

Gearr Aonach »
  • From the car-park, on one of the obvious paths, drop down to the River Coe and aim for the 'Meeting of the Three Waters'. This is a narrow gorge with a bridge and a well-constructed metal set of steps leading to it.
  • Cross the bridge and follow the path, aided with posts and wire initially, uphill through woodland. Exit the woodland through a deer-fence and the centre buttress of the Three Sisters dramatically looms above. Further on the path splits , keep right and follow the higher of these.
  • The path comes to a small cairn and splits again, take the right-fork over grass and through ferns aiming uphill.
  • As the path gets closer to the base of the buttress, it turns left and winds its way uphill south-west for around 150m before turning northwards. First obstactle is encountered - the path climbs under some rock-bluffs, then turns sharply left to follow a ledge uphill. Above this, the path levels and continues for 100m or so northwards to turn once more, this time there's some scrambling ahead, nothing too difficult, just some rocks to clamber up.
  • The route aims south-west again for another 150m or so, and comes to another turning (there is a path continuing on - ignore it, it's a dead-end). Ahead is a bit exposed and the trickiest part of the route, with ground falling to the right. North once more, a final turn and thereafter the terrain easies, the path continuing up to point 692m on Gearr Aonach .

Bidean nam Bian »
  • With the scrambling now behind, crossing the crest of Gearr Aonach is a straightforward hillwalk. Gearr Aonach's crest widens as height is gained reaching a vast grassy plateau before the climb up Stob Coire nan Lochan.
  • The climb up Stob Coire nan Lochan has a few little suprises - some more scrambling awaits, though easy and straightforward. The summit affords a fine view of Bidean nam Bian's northern cliffs.
  • Aiming southwards from the summit of Stob Coire nan Lochan, an obvious path is followed. This path meets up with another coming up from Coire nam Beitheach, then aims onwards up rough ground with occasional boulder-hopping.
  • Bidean nam Bian's summit is reached, on which a small pile of boulders make a cairn. Being the highest point in Argyll, views from Bidean nam Bian's summit are amazing on a clear day.

Stob Coire Sgreamhach »
  • Leave Bidean nam Bian's summit and head south-east along a ridge following a path. Narrow at first, and with some easy scrambling, the crest widens further on as height is lost.
  • Reach Bealach Dearg above the head of the 'Lost Valley' and, since this is where you'll return to, this might be a good place to drop-off rucksacks. There views from here are impressive, particulary down the 'Lost Valley' to the Aonach Eagach.
  • On an obvious path, head up more bouldery ground eastwards, taking care not to be drawn by some lose paths too far northwards. Not before long ascent easies and it's onto Stob Coire Sgreamhach's crest, and then the summit cairn .

Return to Glencoe »
  • Return to the bealach , then with care, head down Coire Gabhail - loose steep ground higher up leads to boulder-field, then a constructed path lower down. The path is initially quite steep, but levels out giving fine walking/running is enjoyed down a gradual gradient crossing occasion burns. The Allt Coire Gabhail is crossed and you're into the Lost Valley - a strange but wonderful place where the river disappears into the ground.
  • The path continues down the east side of the glen and further down, the river needs to be crossed - if in spate, retreat back up the glen a bit, into the trees where the crossing is easier. Once over, remain on the path on the west side of the river, there are several points with drops into the gorge below, so take care ! Reach the gate through a deer-fence again and re-trace your steps along the path through regenerated woodland down to cross the River Coe via the bridge over the gorge at the 'Meeting of the Three Waters' and back uphill to the car-park.

Route profile »

Maps and GPX downloads »

Weather forecasts & webcams »

Guided hillwalking events in this area »

Route photos

Central buttress of the Three Sisters of GlencoeCentral buttress of the Three Sisters of Glencoe
At the top of the first slightly awkward moveAt the top of the first slightly awkward move
Some people may prefer the security of a rope on the trickiest section.Some people may prefer the security of a rope on the trickiest section.
The final ledge before reaching the crest of Gear AonachThe final ledge before reaching the crest of Gear Aonach
On Gear Aonach, the Aonach Eagach behindOn Gear Aonach, the Aonach Eagach behind
Heading to Stob Coire SgreamhachHeading to Stob Coire Sgreamhach

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