Glencorse Reservoir, Loganlee Reservoir, Threipmuir Reservoir, Harlaw Reservoir and Clubbiedean Reservoir Loop

This 21 km (13 mile) reservoir circuit in the Pentland Hills is a long but generally straightforward outing, with around 300 m (985 ft) of total ascent spread gradually across estate tracks, reservoir-side paths, moorland edges, and broad hill-foot trails. Although the distance makes it a full-day walk for many people, the terrain is usually much kinder than the mileage suggests, which is why it often feels more like an easy-to-moderate endurance walk than a steep hill day. The route links five of the Pentlands’ best-known waters—Glencorse, Loganlee, Threipmuir, Harlaw, and Clubbiedean—through a landscape of open views, old waterworks, grazing land, and heather-clad slopes beneath some of the range’s higher summits. (pentlandhills.org)

The most practical trailhead for this loop is near Harlaw Visitor Information Point / Harlaw Reservoir car park, Balerno, EH14 7AS, with Threipmuir Reservoir car park, EH14 7JT as another logical nearby start if parking at Harlaw is full. Those are the nearest clearly identified access points for this walk, and they sit on the western side of the Pentland Hills Regional Park. (pentlandhills.org)

By car, Harlaw and Threipmuir are the simplest navigation targets, and both are official Pentland Hills access points. Parking can be busy in good weather, so an early start is sensible. By public transport, the usual approach is to take Lothian Bus 44 to Balerno Terminus, then walk through Balerno via Malleny Mills and up Harlaw Road, joining the rough path through Fairy Glen to reach Harlaw House and the reservoir area. The park authority notes there is no train service into the Regional Park and no bus service along the A70 on the north-west side, so the final approach is normally on foot from Balerno if arriving by bus. (pentlandhills.org)

What the route feels like

Starting from Harlaw, the walk usually settles in gently. Early sections around Harlaw Reservoir and Threipmuir Reservoir are among the easiest underfoot, with broad paths and open water immediately setting the tone. These western reservoirs sit below the bulk of Black Hill and the higher Pentland skyline, so even on a relatively easy route there is a strong hill-country feel. The gradients here are mild, and this opening stretch is a good place to find a rhythm before the longer traverse toward Loganlee and Glencorse. (pentlandhills.org)

Beyond Threipmuir, the route becomes more open and slightly wilder in character. Tracks and connecting paths lead across the hill-foot landscape toward Loganlee Reservoir, often with broad views toward Scald Law, the highest point in the Pentlands at 579 m (1,900 ft), and the surrounding ridges. Even if the loop itself avoids the summits, the reservoirs are framed by substantial hills, which gives the walk a much bigger feel than its modest ascent total suggests. (en.wikipedia.org)

Loganlee Reservoir tends to feel more enclosed and remote than Harlaw, sitting deeper in the hills along the Logan Burn. From there, the route continues toward Glencorse Reservoir, where the scenery shifts again: more wooded edges in places, long water views, and a stronger sense of the glen narrowing beneath the eastern Pentlands. The paths here are usually still uncomplicated, but this is the part of the day where distance begins to tell, especially if conditions are wet or windy. (pentlandhills.org)

The inclusion of Clubbiedean Reservoir adds another quieter water body to the circuit and helps round out the full reservoir tour. Compared with the larger and more frequently visited waters, Clubbiedean can feel more tucked away, with a calmer, less expansive atmosphere before the route returns toward the better-known western access points.