page_title: Cemaes Head
section_title: Geology and structure
hierarchical_section_title: Cemaes Head / Geology and structure
caption_attribution_description: English: Cliffs on Cemaes Head, Pembrokeshire Coast
context_page_description: Cemaes Head is a headland and nature reserve in north Pembrokeshire. It lies in the community of St Dogmaels, within the Pembrokeshire Coast National Park. To the west and north it overlooks Cardigan Bay, and to the east Cardigan Island and the estuary of the River Teifi.
context_section_description: Although the headland, when viewed from across the Teifi estuary, is relatively unspectacular, its cliffs, which are most dramatic on its north-western side, and reach over 575 ft (175m) in height, are the highest in Pembrokeshire. This makes the bays below the cliff tops largely inaccessible. The bedrock is composed of Silurian and (mostly) Ordovician sedimentary rocks, more specifically of Llanvirn-Caradoc black mudstone, i.e. some 470 million years old. This rock stretches southwest as far as Newport, but Cemaes Head lies north of the Ceibwr Bay Fault, which runs largely WSW – ENE from Ceibwr Bay to Cardigan.
  These rocks are severely twisted and buckled, with even acute folds, a feature easily seen from the clifftops, though appreciated better from the sea. The soft composition of these sedimentary rocks also means that erosion by the sea through hydraulic action, abrasion and attrition is commonplace, and they are thus largely unsuitable for climbing.
  In 1840, George Nicholson in The Cambrian Traveller's Guide, and Pocket Companion, wrote :
  The coasts on each side of the mouth of the river are uncommonly grand, particularly on the Pembroke side, where rises Cemmaes Head, a promontory of immense elevation.
  The highest part of the headland, at Pengarn (189m / 620 ft), grid reference SN 13214 48500, is marked by a pillar trig point (ref. 2097).
  On the western side of the headland, at the foot of the cliffs, is a stony beach area called Traeth Godir Coch which is exposed at low water.
  The western side of the headland is exposed to the full force of the south-westerly Atlantic weather; the eastern side is sheltered.
  The whole headland to the north of the hamlet of Cippyn is a distinctive area; there is an absence of trees and to some extent hedges; fields have stony boundary banks; properties are small, and there is a general absence of modern development.
caption: Contorted strata on the cliffs at Cemaes Head
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