Whilst mainland Wales is one of the most scenic parts of the UK, there’s also a treasure trove of islands around its coastline that offer something different.
The islands are home to unique fauna and wildlife that can’t thrive on the mainland. From the puffins of Skomer to the red squirrels of Anglesey and the rare flowers of Bardsey, each of the islands offers something special.
In this guide, I’ll share 14 islands around Wales that are worth visiting. I’ll begin with 9 offshore islands that you can visit by boat or bridge and later I’ll share my favourite tidal islands that you can walk to at low tide.
1. Anglesey (and Holy Island)
The biggest island in Wales is Anglesey (Ynys Môn) which sits off the coast of North Wales, connected to the mainland by two impressive bridges to provide road and rail access making it very easy to visit.
At the northern tip, you’ll find Holy Island which is technically a different island since it’s separated by a narrow channel of sea. However, most people would group it in with Anglesey since it’s well connected by road and rail so you barely notice moving between the islands.
Anglesey (including Holy Island) is one of just two islands in Wales with a permanent human population, home to around 70,000 people and has become one of the top destinations in North Wales for tourists.
You can visit Anglesey on a day trip from the mainland, however, I recommend spending a few nights on the island so you can visit all of the different areas. There are several hotels and guesthouses, campsites, and many holiday cottages to rent across the island.
Some of my favourite things to do on Anglesey are discovering its lighthouses, visiting Beaumaris where you’ll find a huge castle, and exploring the tidal islands, some of which I’ll mention later.
2. Puffin Island
Just off the southeast coast of Anglesey, you’ll find Ynys Seiriol, better known as Puffin Island due to the colony of puffins that breed here in summer. There would have been thousands of the iconic seabirds here during the Victorian era when the name was coined, however, today there are more like 150-300.
You’ll also find seabirds such as guillemots, and razorbills on the island for summer, whilst cormorants, shags, and gulls reside on the island year-round.
The island is privately owned so you cannot go onto the island (not least because you’ll disturb the birds), but you can take a sightseeing boat cruise around the island.
All of the boats begin from the pier in Beaumaris and along the Menai Strait to the island. There are currently three operators, you can find out more in my guide to visiting Puffin Island.
You can also see Puffin Island from the shore in Anglesey by heading to Trwyn Du Lighthouse, also known as Penmon Lighthouse.
3. Skomer Island
The next three islands are all part of a group known as the Pembrokeshire Islands. The most famous is Skomer Island which is the largest island in Wales after Anglesey/Holy Island.
It's a protected nature reserve, managed by The Wildlife Trust of South and West Wales, and is best known for its colonies of puffins who breed there in the summer.
It’s also home to around half of the global population of Manx shearwaters which reed in burrows under the ground on Skomer before migrating to South America. You’ll also encounter, gulls, fulmars, and even the occasional chough.
Unlike Anglesey, Skomer Island doesn’t have a permanent human population, however, wardens live on the island to look after the wildlife and facilities.
Being such a famous island, there are multiple boat trips every day throughout the summer from different operators. You can opt for a sightseeing tour which goes around the island or a landing tour where you get to spend the day exploring the island on foot.
See my full guide to visiting Skomer Island for more details.
4. Skokholm Island
The second of the Pembrokeshire Islands is Skokholm Island which neighbours Skomer but is about half the size. It’s also managed by The Wildlife Trust of South and West Wales.
Both Skomer and Skokholm have similar species with puffins, guillemots, and razorbills breeding on both during summer. The only difference is that Skokholm doesn’t have kittiwake.
Unlike Skomer, you can’t go on Skokholm Island, however, you can take a sightseeing trip around it onboard a high-speed catamaran with Pembrokeshire Islands Boat Trips. Skokholm and Skomer are typically combined into one sightseeing trip as they are close to one another.
5. Grassholm Island
The third member of the Pembrokeshire Islands is Grassholm Island which has been managed by the RSPB since 1947.
Grassholm is also an island where seabirds breed and is best known as home to one of the world’s largest Gannet colonies.
It’s the smallest island on this list and the furthest offshore so there are fewer trips here with boats only running 3 times per week between April and July.
The boats are also run by Pembrokeshire Islands Boat Trips who run the trips to Skomer and Skokholm. They do not have a landing permit so the 1hr30 journey will take you around the outside of the island with a guide to point out important landmarks and features.
You can also take a full sightseeing safari of all three of the Pembrokeshire Islands; Skomer, Skokholm, and Grassholm.
6. Ramsey Island
On the other side of St Bride’s Bay to the trio known as the Pembrokeshire Islands, you’ll find Ramsey Island which is the third largest island in Wales, after Anglesey and Skomer.
The rocky sea cliffs of Ramsey Island are home to many special species including choughs, razorbills, Manx shearwaters, and the largest grey seal colony in Wales. However, there are no puffins on the island as they were wiped out over a century ago when a shipwreck introduced rats to the island.
Like Skomer, there are frequent boat trips to Ramsey Island with the option of a sightseeing tour around the outskirts or a landing tour.
Boats run from St Justinians which is near the popular ‘city’ of St Davids. My guide to visiting Ramsey Island has all of the information about the different operators and booking details.
7. Caldey Island
Caldey Island (Ynys Bŷr) sits off the coast of Tenby in Pembrokeshire. This is one of just two islands in Wales with permanent residents (the other being Anglesey), although only 40 people live here.
On the island, you’ll find Caldey Abbey which has been the home of monks for thousands of years. About 20 monks live at the abbey making up half of the island's population.
In fact, Caldey Abbey owns the island, making its money from tourism and from the sale of perfume and chocolate which they make on the island.
They can make perfume because the island is famous for its flowers and has many species that are rare across the rest of the country. It also has rich wildlife, one of the few places in Wales where red squirrels can be found in the wild and home to many birds too.
At the northwest of Caldey Island is a tidal island called St Margaret's Island which is a small nature reserve where seabirds including guillemots, razorbills, and cormorants breed.
Getting to the island is easy, with boats running from Tenby at least once per hour throughout summer (except Sundays). Find out more about how to get there in this guide.
8. Bardsey Island
Bardsey Island (Ynys Enlli) is a remote island located off the Llŷn Peninsula in North Wales. The island has deep religious connections with the nickname ‘the Island of 20,000 Saints’. It was a common pilgrimage destination with three trips here thought to be equivalent to one trip to Rome.
Although now uninhabited with only the island’s wardens living there today, it once had a permanent population with a monastery and provided refuge for persecuted Christians. According to legend, Merlin was buried here.
You can take a day trip to the island throughout summer where you’ll spend up to 4 hours exploring the island where you can see the lighthouse, the ruins of the old monastery, and visit the observatory.
Alternatively, you can stay here for a week where you can rent one of the island's holiday cottages which are rented out by the Barsey Island Trust. The island was one of the first designated dark sky reserves so you can expect beautiful starry skies on a clear night.
Although the cottages are well-equipped, keep in mind that there is no mains electricity, so everything is powered by battery, gas or solar panels.
9. Flat Holm Island
The final offshore island I’ll mention is Flat Holm Island. However, it’s unique among the Welsh islands in that it’s not located in the sea, but in the centre of the Bristol Channel, about 5 miles from the coast of Cardiff.
The island is home to a lighthouse and several old fortifications. It’s also home to rare plants such as rock sea-lavender and colonies of lesser black-backed gulls, herring gulls, and great black-backed gulls.
You might also spot slowworms which look similar to snakes although are harmless to humans so you don’t need to worry.
The two companies offering trips to Flatholm Island are Bay Island Voyages (departs from Cardiff Bay) and Cardiff Cruises (departs from Penarth). You’ll typically spend around 2-3 hours exploring the island.
Once you arrive on the island, you can wander around by yourself or take a guided tour of the island’s history with the warden. There is also a small cafe on the island where you can buy food and drinks.
Best Tidal Islands in Wales
All of the islands I’ve previously mentioned can be reached by a bridge or a boat.
But Wales also has a lot of tidal islands which are only separated from the mainland at high tide. When the tide is out, you can reach them on foot across the causeway.
Important: By their very nature, you can easily get stuck on a tidal island if you don’t plan accordingly. Be considerate and check tide times before you go.
Here are the best tidal islands to visit in Wales:
1. Llanddwyn Island
Llanddwyn Island is a tiny tidal island just off the coast of Anglesey and is one of North Wales’ top things to do.
The island is home to several landmarks including the adorable Tŵr Mawr Lighthouse and the ruins of the Church of St Dwynwen who is the patron saint of lovers. After being unlucky in love, she is said to have lived in a convent on the Island in the 5th century.
See my full guide to visiting Llanddwyn Island for more details.
2. St Catherines Island
St Catherines Island is a tiny tidal island just off the coast of Tenby which can be reached by crossing Castle Beach when the tide is out.
The island is home to St Catherines Fort which was built in the 19th century when it was deemed that there was a threat of Emperor Napoleon III of France using Pembrokeshire’s beaches to launch an attack on Britain.
Today the fort is a tourist attraction which you can visit for a small fee and has also been used in TV shows filmed in Wales including Sherlock.
3. Worms Head
Worm’s Head is a tidal island off the Gower peninsular in South Wales which winds into the sea like a serpent (the name comes from the Old English word ‘wyrm’ which means 'sea serpent’).
The most iconic landmark on the worm’s head is the devil’s bridge which is a collapsed sea cave that connects the furthest part of the headland.
The walk along Worms Head begins in Rhosilli. From here it’s about 20 minutes to reach the start of the headland but can take up to an hour to reach the end of it.
4. Burry Holms
Also along the Gower peninsula, at the opposite end of Rhosilli Bay Beach, you’ll find the tidal island of Burry Holmes.
The island was inhabited as far back as the Stone Age and has been an important place for archaeological discoveries. Old tools, burial mounds, and remains of Iron Age forts have been discovered here.
5. Cribinau
Cribinau is the smallest of the tidal islands I’ve shared here, but it’s also unique in another way in that it’s the only one to be manmade.
It used to be part of a peninsular that was connected to the headland and is home to a medieval church called Eglwys Cwyfan, or St Cwyfan’s Church.
As the tide eroded the headland and came close to the church, an artificial stone wall was built around it to protect it. At high tide, the manmade island and church become surrounded by water, but you can still reach it at low tide by walking across the causeway.
I have put together a full guide on how to visit Eglwys Cwyfan which explains exactly how to reach it.
Related Questions
Is Barry Island an Island?
No, although Barry Island was once an Island, it was connected to the mainland in the Victorian era when Barry Docks was built. Barry Island is no longer an island and is now more like a peninsula.
Is Shell Island an Island?
No, Mochras (more commonly known as Shell Island) is not an actual island but a manmade peninsula created when the River Artro was diverted. Although road access to Shell Island is only possible at low tide, pedestrian access is always possible via Morfa Dyffryn Beach.
Published: 17 September 2023