The Traligill Caves

Ascent — about 150 metres

Difficulty — mostly a moderate walk on a good path, with short rocky sections

Duration — about 2 hours

Start — grid reference [NC 251 216]

This short but varied walk explores the limestone landscape and caves east of Inchnadamph, following paths and crossing some rough ground. Long ago, Norsemen named this valley Traligill, the Valley of the Trolls. The walk takes you past some spectacular cave entrances where rivers shoot into the depths, only to emerge hundreds of metres lower down the valley. Limestone is not common in Scotland, and the valleys around Inchnadamph make up the largest area of limestone scenery in the country, large enough to have sizeable caves.

Park at the car park at Inchnadamph, cross the river by means of the tarmac road bridge and turn right to walk up the track past the front of Inchnadamph Lodge. After a short distance you pass through a gate and continue up the track, passing outcrops of rough grey limestone with ‘clints’ and ‘grykes’ (see box on page 20).

Cross the low concrete bridge across the river and climb up the track. The track has been bulldozed through heathery ridges of moraine — piles of debris left behind by a glacier as it retreated. In the debris are boulders of white quartzite and striped gneiss, carried here by a glacier from some distance up the valley. Follow the track as far as Glenbain Cottage, noting the ruinous prehistoric cairn on a low limestone ridge to the right of the track [1] [NC 26075 21748]. This cairn was built of quartzite boulders rather than the local limestone, probably because the quartzite is much harder and forms solid blocks. It is thought to be a burial cairn, and possibly up to 5000 years old.

Pass Glenbain Cottage and shortly afterwards turn right on a faint grassy track running southwards through a walled field [2] [NC 26452 21543]. In the field are some sinkholes — a sure sign that there is limestone below. Within the field there is a faint Y-junction; take the right fork down and cross the wall through a gap. Follow the track towards the river; don’t cross but turn left (east) and follow a faint path along the top of the grassy bank above the river cliffs. In spring, look out for white flowering mountain avens that grow on the limestone crags.

Perched above a bend in the river, in the middle of the narrow path, is a prominent lichen-encrusted boulder that is made of Lewisian Gneiss, and must have been carried here by a glacier from the slopes of Ben More Assynt, the nearest place where this rock type occurs. Upstream beyond the boulder is a spring where the river emerges from its underground course through the limestone. This is the Traligill Rising and is the main outlet of the Traligill underground river system, with water entering in at least ten places higher up the valley.

Continue a little further along the river bank and drop down into the dry valley just above the spring. The water flows along this river bed only during very heavy rain. The south side of the valley is a cliff of dark grey limestone. In contrast, the north side is a gently sloping slab of pale grey limestone. This slope is in fact a thrust plane; the older, dark grey rock has been thrust over the top of the younger, paler grey limestone. The river follows the thrust plane, as it is the line of least resistance; even underground, much of the river flows along the thrust plane.

Limestone landscapes in Traligill

Rainwater is slightly acid because it dissolves carbon dioxide from the atmosphere. In limestone areas, rain reacts with calcium carbonate in the limestone, gradually dissolving it away. The resulting landscape shows a variety of dissolution features, collectively known as ‘karst’, after an area in Slovenia.

1. Blocks and clefts in the limestone surface are known as ‘clints’ and ‘grykes’.
2. Water seeping into cracks dissolves the limestone, gradually forming underground caves.
3. Small caves close to the surface collapse, forming sinkholes.
4. Caves become connected, forming cave systems into which entire rivers disappear, leaving dry stream beds on the surface. Rivers may flow for some distance through these cave systems, before reappearing from springs or risings.

Walk up the dry, rocky valley to where the dark cliffs almost touch the pale limestone below, and listen out for the sound of water flowing underground. As you near the end of the dry valley, the roar of rushing water grows louder and louder, and soon you reach the Lower Traligill Cave, into which the river disappears [3] [NC 27070 20895]. This is one of several points where water enters the underground Traligill ‘plumbing system’. We do not recommend that you enter the cave, as the rocks are very slippery, and could be dangerous.

From the cave, follow the left river bank upstream until you reach a small footbridge. Cross the footbridge and follow the path up the limestone valley south-eastwards towards the main Traligill caves. Within about 500 metres, you will see three obvious cave entrances [4] [NC 27597 20609] below a flat-topped hill, Cnoc nan Uamh.

The first cave you reach is Uamh an Uisge (Cave of the Water) where the river plunges down a thrust plane in the limestone. Do not descend into this cave, which is very slippery and dangerous. This water flows underground for about a kilometre down to the Traligill Rising. Above the Uamh an Uisge is another entrance, a massive shaft that formed when part of the roof of the cave collapsed. Take great care around the edges. A little further on along the path is the dry entrance of Uamh an Tartair (Cave of the Roaring).

After exploring the cave area, retrace your steps to the footbridge and follow the main track back to Inchnadamph. As you return there are fine views down the valley to Loch Assynt and the peaks of Quinag.

Figures

(Figure 33) Trailigill valley. Painting of walk by Elizabeth Pickett.

(Figure 34) Mountain avens on limestone.

(Figure 35) Moraine by the trackside near Glenbain.

(Figure 36) Glacially transported Lewisian Gneiss boulder above Traligill Rising.

(Figure 37) View west along thrust plane in dry river bed, Traligill.

(Figure 38) Limestone landscapes in Traligill.

(Figure 39) The Lower Traligill cave.

(Figure 40) The Upper Traligill Caves, Cnoc nan Uamh to the right.

(Figure 41) View down the valley to Loch Assynt and Quinag.