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
Pen y Bryn now stands, some 185 metres from the church and the Mŵd in the centre of the village. A high-status structure, associated with 13th and 14th century material and thought to be the royal llys with its domestic and administrative buildings, has been found in the valley bottom, on the other side of the river and some 185 metres from Pen y Bryn. It is by the mound known as y Mŵd, near which in 1811 visible remains were locally supposed to be the palace of the Welsh Princes. Pen y Bryn Pen y Bryn is a two-storey manor house, in