Ulster 1995 - Derryveagh Mountains

The Poisoned Glen Horseshoe

Co. Donegal

The Poisoned Glen is said to get it's name from the Irish Spurge, a poisonous plant which grew along the banks of the stream which drains the glen (very ineffectively). The valley is a glacial trough; a glacier which originated in the Derryveagh Mountains to the south spilled over the cliffs surrounding the glen before heading North and then along the lakes to the West of here. The glen is a classic example of the effects of glaciation. It is a remote and wild location and was the last area in the country in which the Golden Eagle bred with some recorded as recently as 1910. The area is still home to a large herd of native red deer - if you're lucky you may see some but you'll definitely see the deer fence on the weekend.

Proposed Route
The following route is the intended route for this MPC. However, as with all hill walking events, the route may be changed or cut short due to weather conditions etc. Bearing this in mind, please study your map carefully and become familiar with the names and relative locations of the various lakes, mountains & rivers. The terrain is generally very rocky on the hills and very wet/boggy in the valleys. As we are so far north and relatively late in the year, daylight hours will be short so an early start is essential. Keep your patrol together and avoid the very steep cliffs surrounding the valley. Even in good weather, always have a bearing to your destination and follow your progress on the map - the weather can change very quickly up here. The route is within the boundaries of Glenveagh National Park - so please respect fences etc.

Friday - Check-in Point (931 196) to Base camp (929 188)
Limited car parking is available at the check-in with more parking available near the church at 905 205. Given that most people will have had a long drive, the walk to base camp is relatively short - but enough to give your legs a stretch. Turn down into the valley at 924 197. Follow the road down past the roofless Dunlewy Church, keeping noise down as there are a number of houses along this road. The campsite is on the riverbank (929 188) at the bottom of the road just off the hairpin bend.

Saturday -

Base camp to head of valley (950 170)
This walk will be done using day packs. Leave your tents standing. Please ensure that you are carrying at least all the equipment mentioned in the day pack list. Leave base camp initially following the river upstream. Follow a well worn track which gradually moves away from the river to the eastern side of the valley. As you head into the valley you will see the many rock buttresses which were caused by glaciation in the last ice age.

Head of Valley to steep ground (956 165)
The going begins to become more rocky as you head into this smaller valley. You will be beginning to gain height now. The surrounding mountains appear to close around you as you continue into this valley.

Steep ground to Col (958 164)
This is your first major climb of the day. The ground is rocky underfoot and quite steep. Watch your footing and keep your patrol close together as you ascend. Steep cliffs will be on either side as you climb - don't stray onto these but keep to the easier(?) climb ahead.

Col to Spot Height 454 (955 164)
Having gained the col, you can begin to appreciate how very broken and rocky the Derryveagh Mountains are - the scenery is more dramatic closer to the cliffs. The area is criss-crossed by dykes and gullies. Leave the checkpoint and cross broken ground to reach the spot height.

Spot Height to Spot Height 485 (949 164)
Leaving 454 descend initially into the col at 954 163 (note the deer fence) and then climb a little to reach a spot height at 953 162. Then turn onto a more northerly direction towards the spot height 485. You should have a fine view into the valley and across to Errigal.

Spot Height to Lough Atirrive (945 162)
Leave the summit and descend in a southerly direction across rocky ground towards northern tip of the larger of the lakes which nestle in the small valley.

Lough Atirrive to Lough Maumbeg (938 162)
Leaving the lake you cross a heathery/rocky slope which begins to steepen. There a many rocky gullies which you have to traverse - making the walk quite interesting. You will arrive at Lough Maumbeg which is a small lake completely enclosed by a steep sided gully.

Lough Maumbeg to northern summit of Rocky Cap (937 160)
Continue in a south-westerly direction across rocky broken ground. The steepness has eased and you should be towards the middle of the ridge. The summit (unnamed on the map) is marked by a small cairn.

Northern summit of Rocky Cap to small lake (934 157)
Leave the summit in a south-westerly direction continuing across rocky, broken ground. You will reach another gully lake.

Small lake to southern summit of Rocky Cap 592 (934 156)
This lake is best passed to the southern side with a slight climb out of the gully. You shortly gain the southern summit which has quite spectacular cliffs to the west & north so keep back from the edge. The views from here are very dramatic and you should be able to see Lough Slievesnaght below.

Southern summit of Rocky Cap to Lough Slievesnaght (932 152)
Leave the summit in a southerly direction in order to avoid the very steep ground and descend initially towards the Col at 934 152. On reaching the col you can turn towards the lake and pick an easy descent over rocky ground.

Lough Slievesnaght to summit of Slievesnaght (924 148)
The bulk of Slievesnaght rises before you and a climb of 180 metres will take you to the cairn on the board summit ridge. This is the highest point in main part of Glenveagh National Park - Errigal is in a separate section of the park - so the views all around are brilliant. Try to spot Tory island to the North.

Slievesnaght to river junction (914 155)
Descend from the summit via the north-west side with it's smooth rock slabs towards Lough Agannive to meet the Devlin river at 915 151. Continue along the river to the junction at 914 155.

Follow river downstream to campsite (929 188)
Follow the river downstream along the right bank keeping close to the river to avoid the worst of the bog. There is a rough track. The river enters a gorge which gradually deepens - you keep to the track which overlooks the gorge. Check-in on reaching the campsite.


Apart from returning to pick up your car/lift, there is no major hike on Sunday. We would recommend that you consider climbing Errigal using one of the well walked routes. These are marked with sign posts from the R251 at approx. 945 197. A full ascent/descent will take about 3½ hours. Alternatively why not visit Glenveagh National Park or the visitors centre at Dunlewy (906 201).