Pen y Gadair Fawr is an high subsidiary summit of

Waun Fach Waun Fach is, with a summit height of , the highest mountain in the Black Mountains in south-eastern Wales. It is one of the three Marilyns over 600 m that make up the range, the others being Black Mountain and Mynydd Troed. To ...

and the second highest peak in the Black Mountains in south-eastern

Wales Wales ( cy, Cymru ) is a country that is part of the United Kingdom. It is bordered by England to the east, the Irish Sea to the north and west, the Celtic Sea to the south west and the Bristol Channel to the south. It had a population in ...

. Marked by a medium-sized cairn, it is a much more distinguished top than its parent 1.5 km to the northwest. Its high top

Pen Twyn Mawr Pen Twyn Mawr is a top of Pen y Gadair Fawr in the Black Mountains in south-eastern Wales. It lies on one of the many south ridges of Waun Fach. The summit is marked by a pile of stones in an area of sandy soil and heather. Pen y Gadair Faw ...

is about 2 km to the southeast.

Geology

The summit and upper slopes of Pen y Gadair Fawr are formed from the Early Devonian Epoch

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates ...

s of the Brownstones Formation, a division of the

Old Red Sandstone The Old Red Sandstone is an assemblage of rocks in the North Atlantic region largely of Devonian age. It extends in the east across Great Britain, Ireland and Norway, and in the west along the northeastern seaboard of North America. It also exte ...

. Beneath these and forming the lower slopes are the sandstones of the Senni Formation (traditionally the Senni Beds). Mudstone layers within these sandstones are more readily eroded and have given rise to the stepped appearance of parts of the mountain, not least the summit section.

Peat Peat (), also known as turf (), is an accumulation of partially decayed vegetation or organic matter. It is unique to natural areas called peatlands, bogs, mires, moors, or muskegs. The peatland ecosystem covers and is the most efficient ...

has accumulated on parts of the hill in the postglacial period, notably north towards Waun Fach.

Access

The hill is wholly within land mapped under the

Countryside and Rights of Way Act 2000 The Countryside and Rights of Way Act 2000 (c. 37), known informally as the CRoW Act or "Right to Roam" Act is a United Kingdom Act of Parliament affecting England and Wales which came into force on 30 November 2000. Right to roam The Act imp ...

as open country and hence is legally accessible to walkers despite their being no public rights of way leading to it. Mountain bikers can follow the forest roads within nearby Mynydd Du Forest, one of which tops out at 715m, just 0.5 km from the summit, but have no legal access to the hill itself.

References

External links

www.geograph.co.uk : photos of Waun Fach and surrounding area
{{coord, 51.96292, N, 3.14392, W, region:GB_source:enwiki-osgb36(SO215300), display=title Hewitts of Wales Nuttalls Mountains and hills of Powys Black Mountains, Wales Talgarth