Lugnaquilla, Mountain summit in County Wicklow, Ireland

Lugnaquilla is a bulky mountain of sprawling moorland in County Wicklow, rising to 925 metres as the highest point in Leinster. Its broad, grassy summit plateau, Percy's Table, is bounded by two steep glacial corries, the North Prison above the Glen of Imaal and the South Prison above the glen of the River Ow. The Geological Survey of Ireland calls it a slate-capped, granite-rooted, relatively flat-topped mountain, and it is the source of the River Slaney.

The Irish name Log na Coille means 'hollow of the wood', though P.W. Joyce proposed Log na Coilleach, 'hollow of the grouse cocks', which Paul Tempan doubts. Tempan also dismisses any link with the deity Lug. The summit plateau is marked as Percy's Table after Colonel Percy, an 18th-century local landowner.

The mountain attracts numerous hikers throughout the year, with three main starting points offering different perspectives of the Wicklow Mountains landscape.

The mountain can be reached from several starting points that offer different difficulty levels and terrain types. Visitors should check weather conditions beforehand and wear proper footwear, as the routes can be steep and exposed.

The two corries are not on the eastern face: the North Prison looks into the Glen of Imaal to the west and the South Prison into the glen of the River Ow to the south. East of the summit lies Fraughan Rock Glen, a cliff-lined hanging valley falling into Glenmalure. The Irish name Log na Coille means 'hollow of the wood', not a reference to wildlife.