Pembrokeshire Coast Path has a rugged, wild beauty, but in the summer months it truly comes alive as the clifftops become strewn with wildflowers, chattering seabirds swoop and soar, and seals bask on rocks just off the shore
Starting at Porthgain’s pretty harbour – home to a brilliant pub, café and art gallery – take a breezy walk along the coast path to Blue Lagoon at Abereiddy Bay. Set in a former slate quarry, the water turns an enticing greenish blue in the sunshine, making it the perfect spot for a refreshing wild swim.
Discover more walks in Wales with BBC Countryfile Magazine's guide to the best walks in the Brecon Beacons, Snowdonia and Pembrokeshire.
Best wild swimming spots in Britain
Explore the UK's most beautiful waters with our guide to the best places to go for a wild swim.
Blue Lagoon walk
3.8 miles/6.1km | 2.5 hours | moderate | 146m ascent
1. Start
Start from Porthgain harbour, which translates in English to ‘chisel port’, and was once used to export slate from the nearby quarry. Heading towards the south-west corner of the harbour, climb a steep set of steps near an old white cottage, following signs for the Pembrokeshire Coast Path. From here, it’s around a 40-minute walk to Abereiddy Bay and Blue Lagoon.
2. Traeth Llyfn beach
At the top of the cliff, find the remains of former 19th-century quarry buildings, which once supplied slate across the UK and are worth exploring.
Slightly further along, spot an impressive collection of coastal caves – often used by seabirds – and the volcanic outcrop of Ynys Barri.
Keeping to the coast path, continue towards the beautifully remote Traeth Llyfn beach. You can climb down to the beach via steps, but be warned, this stretch of coastline has a powerful current and riptides, so swimming isn’t advised.
3. Blue Lagoon
The next stage of the coast path consists of grassy farmland. Follow the path as it rises then descends towards Blue Lagoon and Abereiddy Bay.
Set in the flooded site of the 19th-century St Brides Slate Quarry, the deep, cold lagoon is now a popular swimming spot managed by the National Trust. The sediment from the slate gives the water a greenish blue hue and the cold waters are popular for swimming, kayaking, paddleboarding and coasteering.
4. Abereiddy beach
Continue towards Abereiddy beach. The small bay is sheltered and the water clean, making it another good spot for a swim. Take the path alongside the car park, following a yellow footpath sign inland on a track to pass Ynys Barry farm and cottages. Staying on the track, head across a small road to climb a set of slate steps into a field.
5. Porthgain
Continue following the yellow signs across the fields to head back towards Porthgain.
Blue Lagoon map
OS Maps: Blue Lagoon walking route
Useful information
Starting point
The walk starts in the village of Porthgain, just a short drive from the tiny city of St David’s. There’s a small, free car park in the centre of the village (SA62 5BN), but it can get busy in peak times. Local 404 bus services run to Porthgain three times daily in the summer.
Terrain
The Pembrokeshire Coast Path is a well-marked trail but the terrain is uneven underfoot, with some rocky and muddy sections along steep paths, so good footwear is essential.
Map
OS Explorer OL35
Swim
Blue Lagoon is an impressive site for a wild swim. Access the water via the edge of the slate quarry. The waters are very deep and cold so swim within your ability, and if you start to feel cold then it’s time to get out.
Eat/drink
Visit the traditional Sloop Inn in Porthgain for hearty pub food and local beers and ales. The Shed Bistro near the harbour is famous for its locally caught fish and chips.
