Set on a craggy private island, this derelict fort off the coast of Pembrokeshire has just hit the market for £400,000 and offers a chance to escape civilisation.

Stack Rock Fort is for sale via Purple Bricks and was last upgraded in 1859. The unusual property is in desperate need of renovation but has bags of architectural charm, with a circular outside wall that sits right on the edge of the sea and offers views across the Milford Haven coast.

Its interior courtyard is currently overgrown with creepers which will need cutting back, but is framed by red brick arches and huge empty windows. Original internal features including vaulted brick ceilings, spiral staircases and stone pillars that run throughout the fort’s three floors. The mainland is a boat ride away.

The island property has military roots that date back as far as the 1500s when Thomas Cromwell proposed using it to defend against a French invasion. Stack Rock Fort was built between 1850 and 1852, and briefly used during WWI before being disarmed in 1929. A few years later the building sold for the grand total of £160 – quite the contrast with its current price tag.

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