Pen Llyn a`r Sarnau/ Lleyn Peninsula and the Sarnau

Site overview: This area is home to a huge variety of marine life including the bottlenose dolphin, the grey seal and the European otter. This is a huge site made up of Pen Llyn (the Llyn peninsula) to the north and the Sarnau reefs to the south, as well as the large estuaries along the coast of Meirionnydd and north Ceredigion. This area is named after the Welsh word for causeway. In total it covers 230km of coastline. The site is made up of reefs, sandbanks and mudflats, lagoons and even a couple of sea caves.

Designation Status
Last Updated
6 June 2017
MPA Type
Special Area of Conservation
MPA Purpose
areas which have been identified as best representing the range and variety within the European Union of habitats and (non-bird) species listed on Annexes I and II to the Directive


52° 43' 25" North,
4° 21' 57" West

Surface Area

1,460.64 km2
(563.96 mi.2 )


467.07 km
(290.22 mi.)

Iconic features protected by this site


  • Atlantic salt meadows (Atlantic salt meadows (Glauco-Puccinellietalia maritimae))
  • Estuaries
  • Intertidal mudflats and sandflats (Mudflats and sandflats not covered by seawater at low tide)
  • Reefs
  • Lagoons (Coastal lagoons)
  • Subtidal sandbanks (Sandbanks which are slightly covered by sea water all the time)
  • Shallow inlets and bays (Large shallow inlets and bays)
  • Sea caves (Submerged or partially submerged sea caves)


  • Grey seal (Halichoerus grypus)
  • Bottlenose dolphin (Tursiops truncatus)


  • Glasswort and other annuals colonising mud and sand (Salicornia and other annuals colonising mud and sand)


  • Otter (Lutra lutra)