Llyn Cwm Llwch both Pen y Fan and Corn Du and indeed from the spur of Pen Milan to its west. Llyn Cwm Llwch Llyn Cwm Llwch () is a small lake or pool in the Brecon Beacons National Park in Powys, Wales. It is between 1 and 2 acres: much smaller than the two glacial lakes in the west of the Black Mountain (range): Llyn y Fan Fawr and Llyn y Fan Fach. It is of glacial origin, occupying a rock hollow beneath the peaks of Pen y Fan and Corn Du in the central Brecon Beacons. It is drained by the
Namadgi National Park of Canberra's water. In this sub-alpine region the weather ranges from cold winter nights to warm summer days, and it can change very quickly. Snow normally falls on the Bimberi and Brindabella Ranges during winter, and is not uncommon throughout most of the park. The highest mountain is Bimberi Peak at which is the highest peak in the Australian Capital Territory. The national park is classified as an IUCN Category II protected area. "Namadgi" is a local Aboriginal name for the mountains situated to the southwest of Canberra. Aboriginal presence in the area has been dated to at least 21,000