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Walkers on the coast path at Treginnis in Pembrokeshire, Wales
Walkers on the coast path at Treginnis in Pembrokeshire, Wales | © National Trust Images/John Miller

Treginnis walk

This 6-mile walk around the rocky, undulating headlands of Treginnis will reward you with scenic views across to the islands of Skomer and Ramsay. You'll see some of Wales’s oldest rock formations – some dating back over 600 million years – as well as passing an iron-age fort and the relics of a 19th-century copper mine.

Total steps: 8

Total steps: 8

Start point

Porth Clais Harbour, grid ref: SM741242

Step 1

Turn right as you leave the car park and walk up the road, past high blackthorn hedges.

Step 2

At the crossroads, turn left (signposted Treginnis). The landscape is dominated by the igneous outcrops of Carn Llidi, Carn Trefeiddan and Pen Beri. As you pass Treginnis Lodge, Skomer Island comes into view to the south across St Bride's Bay.

Step 3

At the sign for Pencnwc Farm, turn right off the road and immediately left, following footpath sign to Porthstinian/St Justinian. Walk through a patch of scrub woodland and past a National Trust sign for Treheinif. After about 55yd (50m), go through a metal gate and follow bridleway signs around the field edge.

Step 4

Continue to follow the footpath out of the far corner of the field, then immediately right through a metal gate. Carn Rhosson (topped by a white pole) and the North Bishop come into view as you walk towards the sea and Ramsey Island. Turn right through a metal gate, along a track and through another metal gate onto the short section of road to St Justinian.

Step 5

St Justinian is the start point for boat trips to Ramsey. Turn left onto the coast path, where you'll be for the rest of the walk.

Step 6

Along the coast path you'll see a small promontory, a coastal Iron Age fort called Castell Heinif, with weathered ramparts just discernible. Continue south through two more kissing gates. After the second, the path bears right past Seal Bay – look out for seal pups in late summer and early autumn.

Step 7

A steep descent past a short fenced section of cliff brings you to an open grassy area and the ruins of a 19th-century copper mine. Follow the coast path south and then east. As you bear left you can see Skomer, Midland Isle and the Marloes Peninsula in the distance.

Step 8

Round the corner, you'll walk through some fine coastal heathland and down to the rocky cove of Porthlysgi, an area noted for its shipwrecks. Just east of Porthlysgi, see if you can spot the picrite boulder, a glacial erratic boulder transported here by ice and believed to originate from Scotland. Follow the coast path round to Porth Clais Harbour and back to the car park.

End point

Porth Clais Harbour, grid ref: SM741242

Trail map

A map of the Treginnis walk
Treginnis walk map | © Crown copyright and database rights 2013 Ordnance Survey

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View from Carn Llidi over Whitesands Bay, Pembrokeshire, Wales, with Ramsey Island in the distance.

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Cotswold Outdoor

We’ve partnered with Cotswold Outdoor to help everyone make the most of their time outdoors in the places we care for.

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