Flat Holm Island is located in the Bristol Channel, about 4 miles from the coast of Cardiff. Known for its rich history and diverse wildlife, it offers a peaceful retreat from the mainland. The island features rugged coastal scenery, walking trails, and important habitats for seabirds and rare plants. Historically, Flat Holm has served various roles – from a quarantine station and a Victorian lighthouse to a World War fortification. Today, it is accessible by boat tours, making it a unique day trip.
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Flat Holm Island or Ynys Echni (its Welsh name) is just 4 miles off the coast of Cardiff. It is rich in wildlife and has a lot of history dating back to the 6th century, which is fascinating. From Viking raiders, a Victorian fortification, to becoming the first line of defence. Protecting Cardiff, Penarth, Barry and Newport during the Second World War.
Flat Holm – A Walk Through Time
Before Flat Holm was Flat Holm, it was Braden Relice. This was the name used in the Anglo-Saxon Chronicles. The island is the most southerly point in Wales, and the sea between Flat Holm and the neighbouring island of Steep Holm is the border between England and Wales. It is only 500 metres across, an essential site for scientific interest, and is a nature reserve.
It was on my list of ’30 things to do before I’m 30′ and at 35, I still have not made the short trip across the waters. (Update: I am now 41 and still desperate to visit!) Having sat through an interesting talk on the island in the summer of 2019, it has re-ignited and inspired me to take the short voyage.
The Bronze Age
An axe head has been found on the island; it is believed to be from the late Bronze Age between 900-700 BC. As there is little other archaeological evidence, it is not known if the island was settled during this time.
Holy Visitors
The earliest known visitor to Flat Holm was St Cadoc, who made frequent visits to the island in the 6h Century for meditation. It is also believed that he may have had a small dwelling on the island. He was born in nearby Cowbridge and was known as Cattwg Ddoeth, “The Wise”. Many places in Cardiff from schools to hospitals are named after him.
Viking Invaders
In 918, Viking invaders were pushed back by the Saxons at Watchet, the harbour town in Somerset. In their defeat, they took refuge on the islands of Flat Holm and Steep Holm. Here, many of them starved to death, as they quickly became very short of food. Some of them escaped to Dyfed and from there moved to Ireland.
Farming and The Farm House
Monks from St Augustine’s Abbey in Bristol established a dairy farm and grange on the island after Flat Holm was granted to them in 1150. In other words, the land was farmed for hundreds of years and even had cows, bulls, sheep, horses, pigs and dogs living on it. In 1897, the Farm House was converted into the Flat Holm Hotel. It even had a bar and a skittle alley. The hotel, unfortunately, was closed after a few years. More recently, the Farm House has been converted into accommodation for visitors staying on the island.
Medieval Grave
In a chance find in 1942, a medieval grave was found built into the base of the south wall, which forms a boundary to the garden. The original is now in the National Museum of Wales, but a replica can be found on the island. It is a cross slab in limestone and is of a Latin equal-armed cross with a central dot.
Piracy and Smuggling
During the 18th Century, the island was used for smuggling. An old mine shaft on the north side of the island connects with a series of natural tunnels and has a concealed exit to the sea. Although Flat Holm is in full view of both the Welsh and English coasts, customs authorities were powerless to act as they had no boat to take them to the island. After that, it is believed that the cave in the east cliff was used for storing contraband, mainly tea and brandy.
The Lighthouse
With strong tides and being the gateway to South Wales – Newport, Barry, Penarth and of course Cardiff – having a beacon became essential. The need for a lighthouse on Flat Holm Island had been discussed for many years by leading shipmasters. They forwarded a petition to Trinity House Lighthouse setting out the dangers to navigation and the general desire for a light on the island. After several disasters, it was agreed.
The first time the light was turned on was on the 1st December 1737. Firstly it was powered by coal, which was carried up from the stores by the keepers to the top of the tower. It consumed large quantities, too. 25 tonnes of coal were brought to the island each month.
In 1820, the tower was adapted. A new fixed light was changed to white, and coal was replaced by an oil-burning lamp. In 1881, the light was converted to a clockwork mechanism that has a pattern of white and red group flashing three times every ten seconds at a range of 21 miles. It remained this way until 1969, when the lighthouse was converted to electricity. Finally, in 1997, the light was changed to run on solar power.
The Victorian Fortification
In the 1850’s there were serious concerns that France might attempt to invade the United Kingdom. Formulated by Lord Palmerston, who set up the Royal Commission on the Defence of the United Kingdom. In 1860, the Royal Commission recommended that Flat Holm be part of the strategic coastal defence system for the Bristol Channel. Preparations for the construction began in 1865 and were completed in 1869. Despite millions being spent, an attack never occurred.
Moncrieff Disappearing Carriages were installed on Flat Holm. Each of these carriages carried a 7” Rifled Muzzle Gun. It meant that it was difficult for an enemy ship to locate and range its guns and that the crews that operated them were protected while servicing or reloading. However, the guns were only ever fired in tests. Most of the weapons were easy to dismantle and were sold for scrap, but some do remain on the island.
The Barracks
During the fortification, administrative buildings and a barracks were erected. It was built to house 50 soldiers. But, it never had more than 5 or 6 people staying in it, the Master Gunner and five gunners. With no natural source of water on the island, an impressive tiled water-catchment area was constructed, sloping towards a large underground water storage tank.
Today, water is collected off the roofs of the buildings, but the container is still used to provide the island with fresh water. The Barracks still stand today and are used by those wanting to stay overnight on the island.
The Hospital
Many Cardiffians are aware that there was a cholera hospital on the island, but often get it mixed up and believe it was during one of the World Wars. In fact, it began in 1883 when it was used as an isolation hospital to protect the mainland against the cholera epidemic. Then, Cardiff was a bustling port, with ships coming into Cardiff Bay from all over the world to transport coal. So, moving those with Cholera away from the active ports would have been a priority. In other words, infected vessels would often be moored off Flat Holm, and the patients removed and taken to Flat Holm’s hospital.
However, the facilities were insufficient, and a new hospital was built in 1896. The main building consisted of two six-bed wards and an additional four-bed ward. A laundry room and wooden crematorium were also constructed. The Ministry of Health, therefore, condemned the building in 1935.
Messages Across the Water
The island is probably most famed worldwide for 22-year-old inventor Guglielmo Marconi, who brought his telegraphy system to Britain. He had failed to interest the Italian Government. But after an introduction to William Preece, a Welshman, who was Chief Engineer in the Post Office, he came to Flat Holm with his assistant George Kemp in May 1897.
Marconi successfully transmitted the first-ever wireless messages across the sea, from Flat Holm to Lavernock Point – making telecommunications history. He sent an initial message in Morse code. It read: “CAN YOU HEAR ME”. Shortly after, Marconi received a reply from Kemp: “YES LOUD AND CLEAR”. The recording slip for the first message is now kept at the National Museum of Wales.
The Fog Horn Station
The powerful compressed air fog signal was built and installed in 1908 on top of a cottage. This building can still be seen today and has much of the machinery still present; however, it does need a new roof. The signal was used to warn passing boats of the presence of other vessels and coastlines in foggy conditions. Unfortunately, the horn has not sounded for some time. However, the cottage has recently been renovated and has been dressed by John Lewis, and can now be booked for overnight stays.
Prisoners of War
During the Second World War, the island again became vitally important. Re-fortification began in early 1941, and the construction of gun positions continued throughout 1942. Over 350 soldiers were then stationed on Flat Holm. A narrow-gauge railway used diesel locomotives and wagons to transport ammunition, materials and provisions across the island.
Full use of the Victorian Barracks was made, changing one of the wards for recreational use with a concert hall, cinema and projection room. Films were shown every fortnight and concert parties held once a month. The Farm House was used as the Officers’ Mess. This is the only time that guns were ever fired in defence on the island, as the stationed officers were the first line of defence when the German’s came to bomb Cardiff. Flat Holm became non-operation in 1944, and in 1945 and 1946 German prisoners of war were removed along with the equipment from the military occupation.
(I have not been able to find out much about the prisoners of war, so if you know more or can point me in the right direction, I would love to know?)
Wildlife – Site of Special Scientific Interest and Local Nature Reserve
Did you know the Wild Leek is the flower of Cardiff? It can be found growing on Flat Holm, one of five places in the United Kingdom, along with other rare species of plant such as the Wild Peony.
During the spring and summer months, the island is home to a significant breeding colony of Lesser Black Backed Gulls, with over 3,500 birds calling it home. Herring Gulls mark their territories on the cliffs, waiting patiently for their life mate to return so they can re-connect and breed in the spring. Currently, there are 300 pairs on the island.
Wardens living on the island document the animals they see, including a variety of breeds of caterpillars, rabbits and even Common Lizards. In the early part of the year, they watch flocks of finches and thrushes dine on berries, seeds and snails (which there is a lot of on Flat Holm).
Flat Holm on TV and Film
The island has been featured in historical documentaries and nature-focused programming, highlighting its ecology, heritage landmarks, and social history.
Flat Holm Island Torchwood
Torchwood is the spin-off show of Dr Who. Both were / are filmed in several locations in Cardiff and South Wales. Flat Holm featured in the show. The lead character, Jack Harkness, secretly used it to care for those taken by The Rift. As the island doesn’t allow vehicles on it, the production team was restricted in what they could take with them.
Visiting Flat Holm
You can visit all year round on the Flat Holm Island Ferry. How to get to Flat Holm Island: pre-organised boat trips are arranged by Cardiff Cruises or Bay Island Voyages for up to 3 hours, depending on the tide times. Generally, between April and October. This will give you a unique opportunity to see the conservation, wildlife, and historic buildings. The Flat Holm jetting has a landing fee of £5 per person. This is payable to the warden on arrival.
Cardiff Bay Boat Tour
The Cardiff Bay Boat Tour offers an hour cruise showcasing the area’s transformation from historic docks to a vibrant waterfront. Departing from Mermaid Quay, the tour provides panoramic views of landmarks such as the Wales Millennium Centre, the Welsh Assembly, and the Wetlands Nature Reserve, accompanied by informative recorded commentary. You can also have an Afternoon Tea at Sea.
Take a Picnic
Devon Hampers, send the best of the South West to your front door. The cream tea and afternoon tea hampers include scones, clotted cream and jam. There are also cheese hampers, chocolate, cider and BBQ hampers.
Devon Hampers Promo Code
Get 5% off hampers or create your own. Order anything from a clotted cream tea for two or a large hamper full of goodies. There is no minimum order amount. Use DEVON5 at the checkout.
Flat Holm Island Retreat
So, you can even stay overnight. Flat Holm accommodation in a dormitory is available in the Farm House. It can sleep up to 24 people. You can also camp in the Farm House paddock. Or, stay in the Grade II-listed Fog Horn Cottage. The self-catering cottage offers a double bedroom, a twin bedroom and a lounge with a sofa bed. So, it can sleep up to 6 guests. It has been furnished in partnership with John Lewis. It boasts a biomass boiler for heating, a private garden with a stone BBQ. In addition, incredible views.
You can get further information from the Cardiff Harbour Authority. Contact 029 2087 7912.
Lottery Funding – Re-engaging Cardiff with the forgotten island
Cardiff Council, which manages the island with the Flat Holm Society, has recently been given National Lottery Heritage Funding. To look after Flat Holm’s wildlife and heritage, and to communicate its fascinating story to people on and off the island. They have created a survey to gain insight into your views of Flat Holm. The study results will be used to improve visitor experiences and facilities on the island.
Who Lives on Flat Holm Island?
Flat Holm Island is home to The Warden. They live on the island with a team of volunteers, and their primary role is to conserve the island’s natural and cultural features, including being a handyman, barman, and occasional tour guide on the island.
The Flat Holm Blog
Finally, the Warden and the team post their updates on Facebook, Twitter and Instagram.
Want to know more?
So, A Walk Through Time Flat Holm to Brecon has a fascinating collection of old photographs and contemporary images and begins with a boat trip to the fascinating offshore island of Flat Holm.
Day Trips from Cardiff Wales
There are plenty of days out in Cardiff, but if you’d like to go further afield, Wales is filled with natural beauty and fascinating history, and Cardiff is a brilliant base for day trips within the country. So, consider these destinations if you’re looking for day trips in South Wales:
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Great post 🙂
Thank you very much, good to hear you enjoyed it. I loved writing this one.