Two of the designated sites were batteries alone, with no tower structure at all, which gives the numbering a slightly ghostly quality. Tower No. 16 was the southern terminus of that system, its guns trained to overlap with those at Williamstown to the south and the Pigeon House Fort just over a mile to the north across Sandymount Strand.

The tower was built in 1804 as part of a programme of coastal fortification prompted by the threat of Napoleonic invasion. Construction of the Dublin-area Martello towers, a design of low, thick-walled circular forts developed partly in response to the difficulty British forces had experienced capturing a similar tower at Mortella Point in Corsica, was overseen by Colonel Benjamin Fisher of the Royal Engineers, and by December 1805 all towers in the network were armed and complete. This one is built of cut granite, with a western doorway protected by machicolation, a projecting parapet feature that allowed defenders to drop stones or other material on anyone attempting to force entry. A string course, a narrow projecting band of stonework, marks the parapet level, where a traversing platform once carried twenty-four pounder guns. By the mid-1860s the tower had been disarmed and let to the Earl of Pembroke, who was the landlord for the wider Sandymount area. It was subsequently acquired by the Dublin Tramways Company, a transition that says something about how quickly the Napoleonic-era coastal threat faded from practical concern.

The tower sits close to the foreshore and is visible from the road at Sandymount. Taylor's 1816 map of the environs of Dublin, surveyed at two inches to the mile, shows it already marked in its coastal position not long after completion. The tidal flats of Sandymount Strand spread out to the north, and on a clear day the sight lines that made this location strategically useful, across the bay toward the Pigeon House, are still easy to read. The structure itself is worth examining closely for the machicolation above the doorway and the quality of the granite coursing, details that reward a slow circuit of the building.