Cloughmore or Cloghmore (from Irish An Chloch Mhór 'the big stone'),[1] known locally as "The Big Stone", is a huge granite boulder perched on a mountainside almost 1,000 feet (300 m) above the village of Rostrevor, County Down, Northern Ireland.[2] It sits on the slopes of Slieve Martin in Kilbroney Park, overlooking Rostrevor Forest, Carlingford Lough and the Cooley Peninsula. It is popular destination for visitors, and is part of a National Nature Reserve and Area of Special Scientific Interest.[3]
The granite boulder, which has a calculated mass of 50 tonnes,[4] is a glacial erratic, thought to have been transported from Scotland (from an island in Strathclyde bay)[5] and deposited about 10,000 years ago by retreating ice during the last Ice Age.[2] It sits on a relatively flat area of Silurian metasedimentary rock.