Known in English as Bardsey Island, Ynys Enlli ('The Island in the Currents') sits just under two miles off the westernmost point of the Llŷn Peninsula in West Wales.
The island has a long human history but today is most widely celebrated for its wildlife and craggy scenery.
So special is Bardsey that it has been designated as a National Nature Reserve, a Site of Special Scientific Interest, part of a Special Area of Conversation and a Special Protection Area.
Visitors can come for a day or stay longer for a proper dose of island life. Find out more with our guide to the island, including where it is, the ferry and wildlife highlights.
Where is Bardsey Island?
Bardsey sits two miles off the Llŷn Peninsula in West Wales. It is separated from the mainland by Bardsey Sound.
How big is Bardsey Island?
The island is 1.5 miles long and just over half a mile across at its widest point. Barsdey's highest point, Mynydd Enlli, stands 167m above sea level, offering fine views of the surrounding island, sea and mainland mountain-scape.
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How to get to Bardsey island: ferry and boat trips
You can arrange day or residential visits to Bardsey throughout the summer months. The small island lies two miles from the end of Pen Llŷn across a turbulent sound and crossings only take place when conditions are right.
What to see on Bardsey Island?
Bring a spirit of adventure and expect to share the island with peace-seeking pilgrims following in the footsteps of the earliest Christians, whose medieval followers left a now ruined Augustinian abbey.
The mainland mountains look glorious from the top of Mynydd Enlli, the island’s only hill. From here, spray indicating perilous currents in the dark sea below resembles puffs of flour spilt accidentally on a slate floor.
Bardsey island wildlife
Bardsey belongs to the seals – you know it even before your small boat has docked. Apparently unconcerned by its intrusion, the seals continue their melancholy singing and less melodic snorting. After all, the boat is a regular, pulsing to and from the mainland with visitors, sheep or groceries. But the seals – a colony of some 200 Atlantic grey seals – are a constant.
Harbour porpoises, bottlenose and common dolphins and, on sunny days, Risso’s dolphins can be seen zipping through the deeper offshore waters.
Other marine species include sponges, sea squirts, and the rare yellow star anemone while more than 350 species of lichen grow on the island – including rare ciliate strap lichen.
But Enlli’s wildlife renown is largely due to its 20,000-strong breeding colony of Manx shearwaters. Clumsy on land but streamlined in flight, each pair raises a supremely fluffy chick in an old rabbit burrow before migrating to South America for winter.