Llyn y Fan Fach of the Lady of the lake in Welsh and English. Llyn y Fan Fach Llyn y Fan Fach (Welsh meaning "Lake of the small hill") is a lake of approximately 10 hectares on the northern margin of the Black Mountain in Carmarthenshire, South Wales and lying within the Brecon Beacons National Park. The lake lies at an altitude of approximately , immediately to the north of the ridge of the Carmarthen Fans. It is the smaller of two lakes within this mountain massif: the slightly larger Llyn y Fan Fawr is about to the east. The lake is overlooked by
Pen y Fan the Welsh Government. Toilet facilities are available at the site. A footpath connects the Storey Arms centre, bus stops and the Pont ar Daf car park to the path leading to Corn Du and Pen y Fan. The summit lies on a ridge stretching from Talybont Reservoir in the east, to the A470. About to the south-west lies the subsidiary top of Corn Du, beyond which the terrain drops at a moderate angle to the subsidiary top of Y Gyrn then more steeply to the Storey Arms on the A470. To the east, the ridge drops steeply to the col