Llyn y Fan Fawr

Llyn y Fan Fawr is a glacial lake in Powys, Wales, lying at the foot of Fan Brycheiniog in the Black Mountain range. It sits within the Brecon Beacons National Park at about 605 metres above sea level. The lake was formed by glacial action and is one of the largest of its kind in southern Wales. Its name in Welsh means ‘great lake of the peak’. The surrounding land is mostly peaty, making the ground wet underfoot. The lake is home to rare plants such as shoreweed and quillwort, while greater water-moss grows on boulders at the water’s edge. Freshwater limpets, caddisflies and leeches also live here. A 17th-century manuscript claims the water is so pure that no fish can survive in it. The lake’s only outflow is the River Tawe, which carries water away from its surface. The Beacons Way, a long-distance trail, passes along the ridge above the lake. A lower route winds around the eastern side, offering a closer view of the water. The wet peatland around the lake supports a quiet, natural setting. Visitors find few signs of human disturbance, only the sounds of wind and water. The steep slopes of Fan Brycheiniog rise sharply behind the lake, adding to the wild beauty of the place.