Poisoned Glen

The Poisoned Glen is a steep-walled granite valley running south-east from Dunlewey, closed at its head by cliffs and floored with wet bog. The name has attracted a lot of invention - stories about a poisoned lake or a slain giant - but the likeliest explanation is a translation slip: An Gleann Neamhe, the heavenly glen, misread as An Gleann Nimhe, the poisoned glen, by a mapmaker who mistook one word for the other. Irish spurge grows here and is mildly toxic, which has kept the darker version alive. At the entrance stands the shell of Dunlewey Church, a nineteenth-century Church of Ireland building of white marble and blue quartzite, roofless since the 1950s and one of the most photographed ruins in Donegal. Walking into the glen means crossing genuinely deep wet bog on no path at all, and the granite slabs at the head are used by climbers.

What you actually see

• The granite walls - a steep amphitheatre closing the head of the glen.
• Dunlewey Church - the roofless white marble shell at the entrance.
• The bog floor - deep, wet and pathless.
• Errigal - rising directly above the northern side.

When to go

May to September, when the ground is at its driest, which is relative - it stays wet. Clear weather matters; the glen is oppressive and featureless under low cloud.

Honest expectations

There is no path - the floor is deep wet bog and boots will not keep you dry. The church ruin is unstable and fenced in parts. Midges are severe on still days. Parking is a handful of roadside spaces.

Nearby

Errigal is directly north; Glenveagh National Park is east and Gweedore west.