At the eastern end of the entrance to Fishguard Harbour Dinas Island juts out like a sentinel at the gate.
At its northern tip is Dinas Head where the 465-feet high cliffs look north up the wide arc of Cardigan Bay, the Lleyn Peninsula of Anglesey visible on clear days when even the top of Snowdon can be seen.
Dinas Island is separated from the mainland by a boggy stream running through a deep valley between Cwm-yr-Eglwys (Church Valley) in the north and Pwll Gwaelod (Bottom Pool) to the south. The two mile trek from one to the other around the cliffs is a very popular stretch of the National Park Coastal Footpath, its steep climbs and descents providing plenty of lung-opening exercise and the views giving full value for the effort. The island was farmed during World War Two by the author and naturalist the late Ronald Lockley, famed for his brief residence on Skokholm Island and his writings about his island life. In his later life he lived at Orielton, near Pembroke, where he founded a wildfowl pool and made a comprehensive study of the life of the rabbit, a work which inspired Richard Adams to write the novel Watership Down, which was later made into an animated adventure film.
Cwm-yr-Eglwys has an interesing history because the little 12th century seaside church of St Brynach, which gives it its name, became a victim of the sea during horrendous storms which hammered the coast in 1859, also causing the wreck of the Royal Charter off the North Wales coast.
It was not the first time the church had been destroyed, for the Vikings knocked it down almost a millennium earlier. In 1979 another violent storm did further damage and only the belfry, west wall and part of the churchyard now survive. Now bathers change and picnic on the green sward of the churchyard, only a few feet above the beach, which has earned a Seaside Award and a Green Coast Award, similar to the Blue Flag beach accolade. A narrow slipway is used for launching small boats, for which the bay is a safe harbour in summer weather.
The local boat club organises sailing events and regattas during the first two weeks of August every year. Sheltered from the prevailing winds, Cwm-yr-Eglwys enjoys its own microclimate, experiencing temperatures a few degrees warmer than other parts of the Pembrokeshire coast, and a fair bit drier, which allows the growth of trees and shrubs of near Mediterranean luxuriance. Of interest to visitors on the seafront is a scale model of a trading vessel of the type that would have sailed these waters at the time of the 1859 storm.
To the east are four bays where budding geologists will find at low tide some of the best examples of wave-cut platforms in the County, while in the valley near Pwll Gwaelod is evidence of an east-west Glacial meltwater channel.