What makes this structure quietly strange is the specificity of its original purpose, and how completely that purpose dissolved. The doorway at first-floor level, reachable only by a retractable ladder, sits beneath a small machicolation, a projecting defensive overhang supported on three angled sandstone corbels, the kind of feature more associated with medieval fortifications than with early-nineteenth-century military infrastructure. The ragged masonry at the parapet corners marks where bartizans, small overhanging turrets, once projected outward; a survey carried out around 1990 recorded them still standing, which means they fell sometime in the three decades that followed.

The tower was built around 1804 to 1805 as one of more than eighty signal stations erected by the British Board of Ordnance along the Irish coast. The entire system, running clockwise from Dublin Bay all the way to Malin Head in County Donegal, was designed to relay warnings of an approaching French invasion fleet using naval signal posts. The Ballylinchy station sat roughly 1.6 kilometres south-east of the town of Baltimore, at a point known as Kedge Point, and communicated along the chain with a station on the east side of Clear Island to the west and another at Toe Head to the east, the latter of which was later converted into a coastguard station around 1830. By the mid-1810s the threat of French invasion had receded, and the whole network was abandoned. The enclosure surrounding the tower, with its distinctive fan-shaped southern end documented on Hamilton's 1806 map, once held a flagstaff and a semaphore apparatus; the Ordnance Survey twenty-five inch map surveyed around 1900 still marks both features, though neither survives. A later two-storey addition attached to the north gable suggests the tower was converted to residential use at some point after it went out of military service.

Within the same enclosure, closer to its southern end, are the remains of a Second World War Lookout Post, designated LOP 29, a reminder that the ridge above Baltimore was considered strategically useful more than a century after the Napoleonic-era tower was abandoned. About 160 metres to the south-east, a well-preserved stone sign reading '29 Eire' survives from the same period. Such signs were laid out across the Irish coast during the Emergency to identify neutral Irish territory to aircraft flying overhead, and this one remains in unusually good condition alongside the older ruins it was built to complement.