Lugnaquilla

Lugnaquilla is 925 metres, the highest point in Leinster and the highest mountain in Ireland outside the Munster ranges. Its summit is not a peak but a wide flat plateau of grass and stone, with a cairn called the Percy Bysshe at the centre, and two deep corries - the North Prison and the South Prison - cut into its flanks by glaciers. The commonest route starts from Baravore in Glenmalure and climbs steadily for about five hours return. The plateau is the danger: in cloud, which is frequent, there is nothing to navigate by and walkers have wandered over the edge of the prisons. Map, compass and the ability to use them are not optional here. The western approaches cross the Glen of Imaal artillery range, which is live and controlled by the Defence Forces; firing times are published and entering the danger area when red flags are flying is both illegal and lethal.

What you actually see

• The plateau summit - flat, broad, and featureless in cloud.
• The two prisons - the North and South corries cut into the flanks.
• The Glenmalure approach - the standard route from Baravore.
• The height - 925 metres, the highest ground in Leinster.

When to go

May to September for the longest daylight and the driest ground. Cloud covers the summit on most days of the year; pick a clear forecast and start early.

Honest expectations

The flat summit is genuinely dangerous in poor visibility - navigate by map and compass, not by sight. Five to seven hours of rough boggy walking. The western side crosses a live artillery range; check the firing schedule and never pass a red flag.

Nearby

Glenmalure and Glendalough are north-east; the Glen of Imaal is west.