Carrickhill Martello Tower, Strand Road, Portmarnock, Co. Dublin

Built to watch the sea, it now watches over a family kitchen, its gun platform replaced by a crenellated parapet that hides a domestic roofline, and its granite and rendering doing double duty as both fortification and finish for a private home.

The tower dates from around 1805, part of the chain of Martello towers thrown up along the Irish coast during the Napoleonic Wars, when invasion by French forces was a real enough fear that the British authorities ordered dozens of these squat circular strongpoints built within sight of one another, each named after a defensive tower at Mortella Point in Corsica that had impressed the Royal Navy with its resilience. The design here follows the standard pattern: a circular plan with walls that taper as they rise, a granite string course and cornice marking out the transition points, and a parapet originally built for artillery rather than aesthetics. At some point in the twentieth century, roughly 1970 by the look of the work, the tower gained a projecting entrance porch, a crenellated extension to the roof, and a two-bay single-storey extension tacked onto its side, all in service of converting a piece of military architecture into somewhere people could actually live.

What survives of the original structure sits somewhat awkwardly alongside these later additions. The pebble-dashed walls retain their granite detailing and the old parapet is still there, if now paired with rendered coping rather than anything defensive. The window openings are a mixture of square and segmental heads with rendered reveals, some fitted with refurbished lead windows and others with plainer uPVC replacements, and an oriel window projects from one face, a bay-like addition that would have been unthinkable in the tower's original military guise. Even the chimney stack, rendered and somewhat unusual in its proportions, speaks to decades of piecemeal adaptation rather than a single moment of design. It is this layering, defensive structure, domestic conversion, further extension, that gives the building its particular interest: not a preserved monument, but a working example of how nineteenth-century military architecture gets absorbed into ordinary life.