St Helens Fort is a Grade II listed sea fort in the Solent near the Isle of Wight, built between 1867 and 1880 as a Palmerston fortification to protect the St Helens anchorage and defend Portsmouth from the French invasion threat. Located at the entrance to Bembridge Harbour, the fort was constructed following the Royal Commission's recommendations to safeguard the strategic waters around Spithead. Though now privately owned and not open to the public, the fort remains accessible at exceptionally low spring tides when a sand spit causeway emerges from the seabed, enabling the annual Fort Walk each August—drawing 4,500 walkers in what became the Isle of Wight's largest spontaneous event. The fort served defensive roles during both World Wars, preserving its operational legacy.
