The tower was one of a numbered chain running south of Dublin, but what sets this particular site apart is the possibility that the military engineers of the early nineteenth century placed their fortification squarely within the earthworks of a much older promontory fort, the kind of coastal enclosure that uses natural clifftops or headlands as its primary defence. If that identification is correct, soldiers loading powder cartridges in 1805 were standing on ground that had been defended for centuries before them.

Construction of the Dublin-area Martello towers, squat round fortifications built in response to the threat of Napoleonic invasion, began in 1804 under the supervision of Colonel Benjamin Fisher of the Royal Engineers, and by December 1805 all towers in the chain were armed and complete. Tower No. 13, as it was designated, sat at the northern end of Clarence Street, with its associated battery positioned roughly 200 yards to the north-east on the shoreline. That battery was a formidable installation: armed with four 24-pounder guns, one 18-pounder gun, and two 10-inch mortars, it was tasked with protecting the original Dunleary Harbour, the small inner harbour that still survives today as part of the far larger harbour whose construction began in the years following the end of the Napoleonic wars. Reverend Stokes, writing in 1893, noted that the tower had stood on the spot later occupied by an unused bridge across the railway, close to the Kingstown coastguard station. The tower itself did not survive to see the harbour's expansion; it was demolished in 1836 or 1837 to make way for the Dublin to Kingstown railway line, one of the earliest railways in Ireland or Britain. The battery, depicted on early nineteenth-century maps on or near the site of what became the Irish Lights depot, disappeared from the landscape around the same period.

Visitors to Dún Laoghaire today will find no physical trace of the tower or battery; the record is entirely cartographic and documentary. Taylor's 1816 map of the environs of Dublin, drawn at two inches to the mile, is the clearest contemporary guide to where both structures stood, and copies are accessible through Irish map archives and libraries. The small inner harbour the tower once defended is worth locating; it sits within the modern harbour complex and its modest scale makes it easy to overlook against the sweep of the Victorian piers. The area around the former Irish Lights depot, to the north-east of the old town centre, marks the approximate position of the battery, though nothing on the ground will confirm it.