At a glance
Black-and-white banded 1838 lighthouse at Penmon Point, south-east Anglesey — free coastal access with views to Puffin Island (Ynys Seiriol), resident grey seals, and Penmon Priory 5 minutes away. 4 miles from Beaumaris. LL58 8RR.
About Trwyn Du Lighthouse
Trwyn Du — Black Point — is the south-east tip of Anglesey, where the island narrows to a rocky headland facing the Menai Strait and the mountains of Eryri. The lighthouse here was built by Trinity House in 1838 to mark the northern entrance to the Menai Strait. Banded black and white, it stands on rocks accessible at low tide with Puffin Island (Ynys Seiriol) as its backdrop — an immediately recognisable subject for photographers and one of the most visited lighthouse locations in North Wales.
The headland is well known for its grey seals, which haul out on the rocks around the lighthouse throughout the year. In autumn, seal numbers build as pupping season approaches; on any calm day, a dozen or more seals may be visible from the coastal path. The narrow strait between Penmon Point and Puffin Island is rich in seabirds — gannets, cormorants, razorbills, and guillemots pass regularly, and terns breed on Puffin Island in summer. Boat trips from Beaumaris circumnavigate the island during the season.
Five minutes from the lighthouse car park is Penmon Priory — a medieval Augustinian foundation with associations stretching back to the 6th-century hermit St Seiriol. The surviving church, a 12th-century dovecote, and a holy well make the priory one of the most complete early monastic sites in North Wales. Beaumaris — with its UNESCO-listed castle, Georgian architecture, and waterfront cafés — is 4 miles west along the Menai coast.
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Frequently asked questions
<span lang="cy">Trwyn Du</span> (Black Point) is a working Trinity House lighthouse at Penmon Point on the south-east tip of <span lang="cy">Anglesey</span>. Built in 1838, it marks the northern entrance to the Menai Strait — the stretch of water separating <span lang="cy">Anglesey</span> from the mainland of Wales. The lighthouse is banded black and white and is one of the most photogenic in North Wales, standing against the backdrop of Puffin Island (<span lang="cy">Ynys Seiriol</span>) directly offshore.
Yes — grey seals are a regular sight at Penmon Point, particularly around the rocks near the lighthouse and on the shoreline facing Puffin Island. The seals haul out on accessible rocks and can often be seen resting or swimming close to shore. They are present throughout the year but are most numerous in autumn and winter. Visitors should observe from a respectful distance and avoid approaching the seals, particularly during the pupping season in late autumn.
Puffin Island (<span lang="cy">Ynys Seiriol</span>) is a small uninhabited island lying 800 metres off Penmon Point. It was once home to a significant puffin colony — giving it its English name — though puffin numbers have declined sharply due to rat predation. The island is now an SSSI managed as a nature reserve, with a tern colony in summer. Boat trips to circumnavigate the island run from Beaumaris in season. From Penmon Point you can see the island clearly and observe seabirds on the water between the two points.
Penmon Priory is a medieval Augustinian priory 5 minutes' walk from the lighthouse car park, in the care of Cadw. The site has Christian associations stretching back to the 6th-century hermit St Seiriol, but the surviving church dates mainly from the 12th century. The priory church is still used for worship and is free to enter. Adjacent to it is a fine 12th-century dovecote — one of the best preserved in Wales — and a holy well. The combination of priory, lighthouse, and seal-watching makes Penmon Point one of the most varied short excursions on <span lang="cy">Anglesey</span>.
Follow the B5109 from Beaumaris (4 miles) to Llangoed and then the minor road to Penmon village and the point. There is a pay-and-display car park at the end of the road at Penmon Point. From the car park, the lighthouse is a 5-minute walk along the coastal path. The priory and dovecote are in the other direction, also a few minutes' walk from the car park. No regular bus serves the point — a car is the practical option, though cyclists can follow the road from Beaumaris.