Llyn y Fan Fach 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 several prominent mountain peaks, especially Picws Du and Waun Lefrith.
Pen-y-fan Pond Pen-y-fan Pond Pen-y-fan Pond is a man-made reservoir built around 1794-6 as part of the engineering works for the Crumlin Arm of the Monmouthshire Canal. The reservoir was used to maintain the water level in the canal. The reservoir is formed by a large earth dam with stone facings, forming banks on three sides of a gentle slope. The outlet to the canal feeder forms a stone-lined, oval tunnel and a valve chamber is set into the bank above. Pen Y Fan Pond Country Park features the reservoir, and provides a circular walk around the lake, and minimal facilities for