Cuilcagh is a mountain on the border between County Fermanagh and County Cavan. With a height of 665 metres it is the highest point in both counties and the 165th highest on the island of Ireland.
Cuilcagh (from Irish: Binn Chuilceach, meaning “chalky peak”) is a mountain on the border between County Fermanagh (in Northern Ireland) and County Cavan (in the Republic of Ireland) (once part of the medieval Kingdom of Breifne). With a height of 665 metres (2,182 ft) it is the highest point in both counties and the 165th highest on the island of Ireland.Water from the southern slope flows underground until it emerges some miles away in the Shannon Pot, the traditional source of the River Shannon.
Cuilcagh Mountain has one of the largest expanses of blanket bog in Northern Ireland, on a relatively high elevation upland landscape, bounded by limestone grassland to the north and montane habitats to the south. The blanket bog exhibits a wide range of characteristic vegetation and structural features, with well-developed pool, hummock and lawn features, acid flushes and bog bursts. The bog vegetation is characterised by luxuriant Sphagnum mosses but over most of the site dwarf-shrubs and graminoid herbaceous species dominate. The Cuilcagh area supports a rich assemblage of upland insects, and is one of the most important sites in Ireland for these species.