Step on to Tenby’s Castle Beach at high tide and St Catherine’s Island is tantalisingly close, yet inaccessible.
However, at low tide, weather permitting, it's possible to explore this marvel of the Welsh coast – and with a long and eclectic history, there's plenty to discover.
Where is St Catherine's island?
St Catherine's Island lies just off Castle Beach in Tenby, Pembrokeshire, Wales.
How big is St Catherine's Island?
St Catherine’s is a dramatic limestone outcrop, 200m long, 60m wide and 28m high. Conquering it means climbing 74 steps to reach a 10m steel bridge spanning the final moat-like ditch defence.
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History of St Catherine's Island
Solitude-seeking 12th-century visitors founded a small chapel here dedicated to St Catherine, but today, it’s the substantial shell of a Palmerston Fort that crowns this incredible islet.
The fort was built in 1867 to protect the naval dockyard at Pembroke and Milford Haven’s deep-water anchorage from a perceived Napoleonic threat, but thankfully it was never needed. Its imposing, black metal doors give it a prison-like atmosphere. Fans of the BBC series Sherlock may recognise the location from the 2016 episode, ‘The Final Problem’, when it doubled as a North Sea prison.
Vast windows overlooking Pembrokeshire’s glorious coastline now fill the gaps once taken by Napoleon-deterring seven- and nine-inch artillery.
The 20th century saw many new guises for the fort. In 1907, the Windsor-Richards family turned it into a luxury home. Step along its central corridor, and it’s easy to imagine the gun casemates on either side making cosy rooms with captivating sea views.
Garrisoned during the First World War, and compulsorily purchased by the government at the outbreak of the Second World War, little remains of its residential history because Harrods auctioned off most of the internal fittings in 1940.
St Catherine's Island zoo
Between 1968 and 1979, the fort housed a zoo with over 100 animals, including monkeys and an alligator. Occasionally, the monkeys escaped and stole from tourists on the beach below.
It’s still a haven for wildlife, with the area below the high waterline designated a SSSI, and the cliffs home to choughs and peregrine falcons.
Visiting St Catherine's Island
For a magical experience, set off from Saundersfoot on a 4.5-mile stroll along the Pembrokeshire Coast Path, culminating at St Catherine’s Fort in Tenby. Take the bus or train back to the start.
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