A circular route around two of the higher Pentland Tops: East Cairn, the highest point in Edinburgh and West Cairn, the highest point in West Lothian. The route is mostly on paths although the descent includes an off path section over moorland.
- Distance: 11 km / 7 miles
- Ascent: 450 m / 1400 feet
- Terrain: Mostly unsurfaced paths but also some off path
- Start / finish: Harperrig Reservoir car park, Cairns, off the A70 near Balerno. Grid ref NT 088 606.
Route Map

Start the walk from the small car park near Cairns House off the A70 (grid ref NT 088 606. Walk towards the house / Cairns Castle where a signpost points you through a pedestrian gate and on to a path around the south shore of the reservoir. This path can be somewhat wet underfoot after heavy rain. Keep on the path until about 200m beyond the house at Baad Park when you should spot a pedestrian gate on your right hand side with an arrow marker post. Go through this gate onto a, sometimes wet, path across the moor. Although unsurfaced the path is easy to follow and there are occasional marker posts.
Soon after crossing a burn this path meets the old Thieves Road route (now incorporated in to the Cross Borders Drove Road). Turn right on to this old right of way and follow it towards the two hills ahead of you. Approximately 500m further on a rough path leads off to your left steeply up the heather slope of East Cairn.
The path up East Cairn is a bit of a slog but it is relatively short and as you reach the summit plateau the large ancient cairn rears up ahead of you. The cairn provides good shelter on a windy day however, it is worth noting that it is not the actual summit of the hill! The real 567m summit is approximately 700m wsw of the cairn and is very unremarkable.
A path leads from the cairn to the summit, and for much of the way follows a wall. The summit is encountered very soon after passing through a gate in wall. On a misty day it would be easy to walk past it as it is not marked with a cairn. If you start to go downhill, you’ve overshot it!
From the summit retrace your steps on the path alongside the wall to the point where the wall turns sharp left down the hill. Go downhill picking up a rough path beside the wall to reach Cauldstane Slap on the Thieves’ Road between East Cairn and West Cairn.
Ascend West Cairn by going through the gate and heading up the left hand side of the wall on yet another rough path. Part way up the wall and path turn right directly towards the summit. This summit is topped with both a cairn and trig point. However, you will have to do a bit of fence climbing (not difficult) to reach them.
The descent is now off path and could be made by simply following the wall down the steep north west side of the hill. However, if you head north for a bit before descending you can pick an easier gradient. The heather soon turns to grass which makes for easier going.
At the foot of the hill you can either stick to the wall and follow it alongside a forest or use one of the quad bike tracks that cross the moorland. If using one of the tracks try not to stray too far to your right away from the forest edge. You need to aim for an obvious old quarry area beside the forest at grid reference NT 098 597.
From the quarry an overgrown track heads across the moor to reach pasture land. At this point it would be sensible to keep dogs on leads. Take care to close gates behind you. The track takes you over fields towards the farm buildings at Cairns House. Walkers are not really encouraged to walk close to the farm (there is a sign but it is for the opposite direction so you will not see it until you’ve passed the farm). Stay away from the buildings/working areas, be sensible and don’t cause any disturbance whilst near the farm.
You will now be back at Cairns House a short distance along the road from the car park.