History & Architecture
Party Island Dreams: Thorne Island Fortress Hits Market for £3 Million
An abandoned 19th-century fortress off the Pembrokeshire coast has been reborn as the ultimate private party island – and it could be yours for £3 million. Thorne Island, once a strategic Napoleonic fort guarding Milford Haven, was left derelict for nearly two decades. But thanks to former software CEO Mike Conner, the 2.5-acre island has been painstakingly transformed into a luxury off-grid escape complete with its own nightclub, helipad, and festival-ready party spaces.
Mike Conner, who bought the fortress in 2017 for £555,000, admits he had no idea of the scale of the challenge. “There was no electric, no water, and any food or waste needed to come back off,” he told the BBC. Workers lived on the island for weeks at a time, charging phones by generator and washing in the sea while renovations were underway.
A Fortress with Festival Potential
After investing years of work and over £200,000 in infrastructure, including drilling through 16ft of rock to install a biodigester pump, the island now boasts a self-sustaining energy system. Solar panels, a 100kWh battery storage unit, air-source heat pumps, and a 250,000-litre rainwater harvesting system make it fully off-grid.
Inside, guests are welcomed into a grand reception hall with vaulted ceilings, exposed brickwork, sash windows, and wood-burning stoves. The island features an open-plan kitchen, a snug, and five bedrooms capable of sleeping up to 20.
But the real draw? The nightclub carved into the fortress, perfect for hosting up to 800 guests without worrying about noise complaints.
Mike Conner even threw his own 50th birthday festival on the island, and he believes the future buyer could transform it into a world-class party venue or luxury tourist attraction.
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From Military Stronghold to Party Island
Thorne Island’s transformation is nothing short of remarkable. Originally designed to defend against French invasion in the 1800s, it later became a quirky hotel in 1947, popular for weddings and stag parties, before falling silent in 1999.
Now, thanks to Mike Conner’s vision, it’s ready for a new era – whether as a private escape, luxury rental, or one of the UK’s most unique event destinations.
A Rare Opportunity
Estate agents Strutt & Parker have listed the island for £3 million, describing it as “a unique blend of history, sustainability, and coastal luxury.”
With panoramic views across the Pembrokeshire coast, historic character, and unrivalled privacy, Thorne Island offers a rare chance to own not just property, but an entire off-grid lifestyle.
As Mike Conner himself puts it: “It has the potential to offer the most unbelievable 24-hour experience.”
