Enjoy Pembrokeshire

Geology Hotspots

Pembrokeshire is well known for it geology where the coastline displays a greater variety of rocks and scenery than any equivalent area in Britain with over 250 miles of exposures.

The landscape is ancient with nearly all the rocks underlying its land surface formed before the end of the Carboniferous period some 290 million years ago.

The oldest date back 600 million years and can be found on the Treginnis Peninsula, south west of St Davids. Rocks younger than 290 million years old have been lost, largely as a result of weathering and marine erosion.

The diversity of the coastal landscape we see today is the result of geological processes and actions such as glaciation, river weathering and marine erosion on this wide variety of rock types.

A small sample of geological gems are included on this site. There are many more for you to explore! If you are interested in fossils then have a look at the more information link on fossils below.

  • Please remember to follow the codes of conduct and advice given below and be aware of cliff falls and rising tides. The Rocks link below gives more detailed information on the geology of Pembrokeshire.
  • The evaluation and selection of the most important sites in Britain for geological study (the Geological Conservation Review) was initiated in 1977 by the Nature Conservancy Council.
  • There are 50 Geological Conservation Review (GCR) sites within the Pembrokeshire Coast National Park, covering approximately 40% of the coastline, as well as a number of inland localities including the source of the Preseli ‘bluestones‘ used at Stonehenge.
  • These sites have been documented and are monitored by Natural Resources Wales (NRW) - the government‘s statutory advisers on nature conservation in Wales. It is estimated that a further 30% of the coastline will qualify for designation as Regionally Important Geological Sites (RIGS). The features of the GCR sites are protected by legislation for Sites of Special Scientific Interest (SSSI).
  • Those of RIGS are covered by local planning guidelines. Please remember these basic rules to ensure that everyone can enjoy our geological heritage and that you do not disturb the tranquillity and beauty of the area.

Top Tips

  • Always obtain permission to visit sites that are not on public footpaths or outside areas open to the public.
  • Please do not hammer rocks or collect fossils unless such action can be justified and does not cause unacceptable visual impact.
  • Remember that causing damage to geological or biological features of an SSSI is a criminal offence - most geologically interesting areas are covered by some form of nature conservation legislation.