Lakes of Ireland: Over 12,000, Led by Lough Neagh

Count & Distribution

12,000+ lakes (loughs) – mostly in the west, northwest, and midlands (glacial scour in Carboniferous limestone & Silurian shale).

Largest

• Lough Neagh – 388 km² (150 sq mi) – largest in British Isles. Borders 5 counties (Antrim, Down, Armagh, Tyrone, Londonderry). Source of 40% NI's drinking water.
• Lough Corrib (Galway/Mayo) – 176 km².
• Lough Derg (Shannon) – 130 km².
• Lough Ree, Lough Mask, Lough Conn, Lough Allen – 100–130 km² each.

Types

• Glacial ribbon lakes (Connemara, Wicklow).
• Limestone solution lakes (turloughs – seasonal).
• Peatland pools (midlands bogs).

Ecology & Use

• Salmon, trout, pike, perch, eel fisheries.
• Water supply, hydro (Ardnacrusha on Shannon).
• Recreation: angling, boating, kayaking, island monasteries (Clonmacnoise, Devenish).

Conservation

EU Water Framework Directive; Invasive species (zebra mussel, curly waterweed) major threat.