The tower here, built around 1804 to 1805 and originally two storeys over a partial raised basement, was never much more than a compact cube, roughly 5.8 metres square on the outside. What gave it its military character were the details now largely lost: corner bartizans projecting from the north face, a first-floor entrance on the south side protected by a machicolation (a projecting parapet with a gap in the floor through which defenders or watchmen could observe what was directly below), and pairs of square-headed windows looking east and west. Today only the ground floor and the stumps of the first floor survive, though the outward bulge in the north wall, built to carry the chimney flue, still betrays the original plan clearly enough.

By the time Samuel Lewis was compiling his topographical dictionary in 1837, the military urgency had long passed. He noted that the building, formerly a signal tower during the war, had become the residence of a Lieutenant Speck, who commanded the coastguard at Dunny Cove. That repurposing left physical traces. An external staircase was wrapped around the south-east corner and across the south wall to reach what had been the original first-floor entrance, and a single-storey outbuilding was added against the west side. The site sits within a U-shaped rubble-stone enclosure, and a small oval extension to the south of it was almost certainly where the signal mast stood. Hamilton's map of 1806 shows the enclosure in its earliest form, narrow and functional; by the time the Ordnance Survey revised at twenty-five inches to the mile around 1901, the site had accumulated further structures, a semaphore position just outside the oval enclosure, a separate flagstaff, and a footpath running to a coastguard station some 365 metres to the east that has since been demolished. The nearest surviving tower in the original chain stands at Seven Heads, about 13 kilometres to the east; the equivalent station to the west, at Goat's Head, is gone entirely. Around the Dunnycove tower, the landscape carries its own longer chronology: the fragmentary remains of Ardfield Church sit roughly 170 metres to the east, and about 1.7 kilometres to the north-east, a tower house marked as Dunnycove Castle on the first Ordnance Survey maps occupies a coastal promontory fort at Dunnycove Point.