Cefn Gwyngul
Geology
The hill lies at the heart of the South Wales Coalfield and is formed from relatively flat-lying sandstones of the Pennant Sandstone Formation assigned to the Warwickshire Group, laid down in the late Carboniferous Period. Numerous coal seams within these beds have been worked in the past and the legacy of coalmining is widespread. The important Brithdir and Brithdir Rider seams outcropped along the upper western flanks of the ridge.
Access
Minor roads ascend the slopes of the hill from Ferndale, Ynysybwl and Pontypridd converging at the elevated hamlet of Llanwonno. Various other public rights of way cross the hill though none reaches its summit. Route 47 of the National Cycle Network runs the length of the hill on its eastern side ascending via the minor road from Pontypridd to Llanwonno and then continuing northwest on forest tracks to join the A4233 above Maerdy. Those areas of forestry in the ownership of Natural Resources Wales (successor to Forestry Commission Wales in 2013) are open to public access, as are some areas of open moorland by virtue of the Countryside and Rights of Way Act 2000.
References
- ^ British Geological Survey 1:50,000 map sheet 248 Pontypridd & accompanying memoir
- ^ "BGS 'Geology of Britain' viewer". Archived from the original on 2 December 2016. Retrieved 14 August 2013.
- ^ Ordnance Survey Explorer map 166 Rhondda & Merthyr Tydfil/Merthyr Tudful