Fan Bwlch Chwyth
Encyclopedia
Fan Bwlch Chwyth is a peak in the Fforest Fawr
section of the Brecon Beacons National Park and within the county of Powys
.
Its summit at 603m is marked by a trig point
at OS grid ref SN 912217.
laid down during the Devonian period. A north-northwest - south-southeast trending fault runs across its north-eastern face.
This face is much the steepest and has its origins in the ice ages when a minor glacier grew at this spot. It has left a couple of arcuate moraines which are readily seen from the track. The glaciated rock face has been quarried. The quarry is designated as a site of special scientific interest
for its geological interest.
and the A4067 road. The bridleway follows, in part at least, the vehicular track (no public vehicular access) to the disused quarry.
Fforest Fawr
Fforest Fawr is the name given to an extensive upland area in the county of Powys, Wales. Formerly known as the 'Great Forest of Brecknock' in English, it was a royal hunting area for several centuries but is now used primarily for sheep grazing, forestry, water catchment and recreation...
section of the Brecon Beacons National Park and within the county of Powys
Powys
Powys is a local-government county and preserved county in Wales.-Geography:Powys covers the historic counties of Montgomeryshire and Radnorshire, most of Brecknockshire , and a small part of Denbighshire — an area of 5,179 km², making it the largest county in Wales by land area.It is...
.
Its summit at 603m is marked by a trig point
Trig point
A triangulation station, also known as a triangulation pillar, trigonometrical station, trigonometrical point, trig station, trig beacon or trig point, and sometimes informally as a trig, is a fixed surveying station, used in geodetic surveying and other surveying projects in its vicinity...
at OS grid ref SN 912217.
Geology
The hill is formed from sandstones and mudstones of the Senni Beds Formation and Brownstones Formation of the Old Red SandstoneOld Red Sandstone
The Old Red Sandstone is a British rock formation of considerable importance to early paleontology. For convenience the short version of the term, 'ORS' is often used in literature on the subject.-Sedimentology:...
laid down during the Devonian period. A north-northwest - south-southeast trending fault runs across its north-eastern face.
This face is much the steepest and has its origins in the ice ages when a minor glacier grew at this spot. It has left a couple of arcuate moraines which are readily seen from the track. The glaciated rock face has been quarried. The quarry is designated as a site of special scientific interest
Site of Special Scientific Interest
A Site of Special Scientific Interest is a conservation designation denoting a protected area in the United Kingdom. SSSIs are the basic building block of site-based nature conservation legislation and most other legal nature/geological conservation designations in Great Britain are based upon...
for its geological interest.
Access
The entire hill is open country across which the walker can wander at will. A bridleway runs south-eastward from the minor road between Heol SenniHeol Senni
Heol Senni is a hamlet in the valley of the Afon Senni just north of the Fforest Fawr section of the Brecon Beacons National Park. It lies within the community of Maescar in the county of Powys, Wales. The Welsh name means the 'road by Senni' and reflects its position near the crossing of the...
and the A4067 road. The bridleway follows, in part at least, the vehicular track (no public vehicular access) to the disused quarry.