Pembrokeshire Coast

Pembrokeshire Coast is the odd one out among Britain's national parks — designated in 1952 for its coastline rather than its uplands, a ribbon rarely more than a few kilometres deep that wraps the whole south-western tip of Wales, nowhere more than sixteen kilometres from tidal water. Its 299-kilometre coast path, proposed by the naturalist Ronald Lockley in 1951 and opened in 1970, walks an extraordinary compression of geological time: Precambrian volcanics on the St Davids peninsula that are among the oldest rocks in Wales, the purple Cambrian sandstones of Caerfai — rocks of the period named for the country itself — Ordovician and Silurian lavas in the headlands past Abereiddi, Old Red Sandstone glowing at Manorbier, and finally the grey Carboniferous limestone platform of Castlemartin, where the sea has cut the Green Bridge of Wales arch, packed the Elegug Stacks with guillemots, and sliced Huntsman's Leap almost to the path. At Broad Haven the strata stand on end in textbook folds, and at St Govan's a medieval chapel is wedged whole into a slit in the cliff, down a stair the legend says can never be counted the same way twice.

Offshore is the park's real capital. The islands keep the Norse names Viking traders left — Skomer, Skokholm, Grassholm, Ramsey, Caldey — and hold seabird numbers of world rank: Skomer and Skokholm together are the largest known breeding gathering of Manx shearwaters on earth, hundreds of thousands of pairs that raft on the evening sea and come ashore only in full darkness, past burrows guarded by day by Skomer's tens of thousands of puffins. Skokholm carries Lockley's other legacy, the bird observatory he founded in 1933, Britain's first; Grassholm, eleven kilometres out, is a white-domed gannet city tens of thousands of pairs strong, hit hard by avian influenza in 2022 and slowly rebuilding. Ramsey belongs to the choughs and, from September, to grey seals — the largest colony in southern Britain pups in these coves and caves — while Caldey belongs to the Cistercians, whose predecessors in various habits have held the island more or less since the sixth century. Coasteering — traversing the intertidal zone by scramble, swim and jump — was invented on the St Davids cliffs in the 1980s and exported from here to the world.

Inland the park rises only once, to the Preseli Hills, and they carry its heaviest history: the spotted dolerite of Carn Goedog and Craig Rhos-y-felin has been matched to the bluestones of Stonehenge, with excavated quarrying at both outcrops dated to the centuries just before the stones rose on Salisbury Plain — however they travelled the 250 kilometres, the source is here, above the Golden Road ridgeway and the great portal dolmen of Pentre Ifan. Iron Age forts crown nearly every headland on the coast below. St Davids, at the peninsula's end, is Britain's smallest city: the cathedral of Dewi Sant, the patron saint of Wales, sits sunken in its hollow out of raiders' sight, and a twelfth-century papal ruling made two pilgrimages here worth one to Rome. The park's complications are honest ones — Milford Haven, the drowned valley Nelson praised among the great harbours of the world, brings LNG tankers past Iron Age promontory forts to terminals excluded from the park by metres, and the Castlemartin ranges close their limestone coast on firing days while keeping it unploughed the rest of the year — and in the wooded Gwaun valley behind Fishguard, cut by glacial meltwater, the farms still toast the new year on 13 January, keeping the calendar Britain abandoned in 1752.

What's worth knowing before you go

Haverfordwest is the bus-and-rail hub, with branch-line stations too at Fishguard, Tenby and Pembroke; in season the coastal shuttles — Puffin Shuttle, Poppit Rocket, Coastal Cruiser — connect the path's trailheads, which is what makes one-way cliff days possible. Time the wildlife honestly: puffins and the other auks are ashore from late April to mid-July and gone within weeks after, shearwaters need an overnight stay on Skomer or Skokholm to see at all, and autumn seal pups mean keeping off flagged beaches. Skomer landings are capped and sell out — book ahead through the Wildlife Trust rather than hoping at Martin's Haven — and the Stack Rocks–St Govan's road opens only when the Castlemartin range is silent, so check the firing times. Surf runs at Freshwater West and Whitesands; the sheltered swimming is Barafundle. The connoisseur's Pembrokeshire is up the Daugleddau, the "secret waterway" above the oil jetties, where drowned oak-fringed creeks wind past Lawrenny to Carew's castle and tidal mill — or out along St Davids Head over Carn Llidi, where the Coetan Arthur dolmen looks down the whole parade of Ramsey Sound.