The Central Wales Lineament is a north–south aligned zone of geological faults and folds which runs for scores of miles through

Wales Wales ( cy, Cymru ) is a Countries of the United Kingdom, country that is part of the United Kingdom. It is bordered by England to the Wales–England border, east, the Irish Sea to the north and west, the Celtic Sea to the south west and the ...

and which gives rise to a number of landscape features. The lineament lies along the axis of the Central Wales Syncline, both following the generally northeast–southwest Caledonide trend though its central section is more north–south aligned. The Tafolog Fault which runs north from

Llanbrynmair Llanbrynmair () is a village, community and electoral ward in Montgomeryshire, Powys, on the A470 road between Caersws and Machynlleth. Llanbrynmair, in area, is the second largest in Powys. In 2011, it had a population of 920. Description The c ...

is one component structure in the central section of the

lineament ''See also Line (geometry)'' A lineament is a linear feature in a landscape which is an expression of an underlying geological structure such as a fault. Typically a lineament will appear as a fault-aligned valley, a series of fault or fold-aligne ...

and along which Cwm Tafolog has been eroded. The Dylife Fault, a southerly continuation of the same fault is coincident with the valley of the

Afon Twymyn The Afon Twymyn ( en, River Twymyn, italic=yes) is a river in Powys, Mid Wales. From its source at the 40-metre high Ffrwd Fawr waterfall and head of the Pennant Valley near Dylife the river flows through Llanbrynmair before joining the Rive ...

. The section of the valley east of the former lead-mining village of

Dylife Dylife is a former mining settlement in Powys, Wales, located at the head of Afon Twymyn in the Cambrian Mountains, one mile west of the road between Llanidloes and Llanbrynmair ( B4518). It is in the historic county of Montgomeryshire. The near ...

is spectacularly incised into the landscape making this one of the most readily recognisable parts of the lineament. The lineament continues southwards as a series of offset north–south faults, crossing the

Wye valley The Wye Valley Area of Outstanding Natural Beauty (AONB; cy, Dyffryn Gwy) is an internationally important protected landscape straddling the border between England and Wales. The River Wye ( cy, Afon Gwy) is the fourth-longest river in th ...

just west of

Llangurig Llangurig is both a village and a community in Montgomeryshire, Powys, Wales. The population was 723 in the 2011 UK Census. The community includes the hamlet of Cwmbelan. The River Wye, the A470 and the A44 trunk roads pass through Llangurig, ...

. The lineament continues south passing through the top end of

Cwm Ystwyth Cwmystwyth (also Cwm Ystwyth, ; en, "valley of the River Ystwyth") is a village in Ceredigion, Wales near Devil's Bridge, and Pont-rhyd-y-groes. The Ordnance Survey calculates Cwmystwyth to be the centre point of Wales (; ). History Dis ...

where it meets the head of the

Elan valley The Elan Valley ( cy, Cwm Elan) is a river valley situated to the west of Rhayader, in Powys, Wales, sometimes known as the "Welsh Lake District". It covers of lake and countryside. The valley contains the Elan Valley Reservoirs and Elan Villa ...

and then southwest where its main component is the Claerwen FaultBritish Geological Survey 2012 ''Rhayader'' England and Wales sheet 179 Bedrock & superficial deposits 1:50,000 (Keyworth, Nottingham: British Geological Survey)

References

{{reflist Geology of Wales