That view is not incidental; the geometry of the two towers was deliberate, each positioned to cover the coastal approaches and landing places that nervous British military planners considered vulnerable in the early nineteenth century. What makes this particular tower quietly odd is everything that came after its military life ended: a coal depot, then a home, then tearooms, and eventually the focal point of a holiday camp that ran from the 1950s into the early 1970s. Few fortifications designed to repel a Napoleonic invasion end their days surrounded by summer holidaymakers.

The tower is recorded as Skerries Martello Tower No. 11, one of twelve constructed north of Dublin as part of a coordinated coastal defence programme. Construction commenced in 1804 under the supervision of Colonel Benjamin Fisher of the Royal Engineers, and by December 1805 all the Dublin-area towers were armed and complete. Each mounted a single 24-pounder cannon, with the exception of the tower on Ireland's Eye, which carried two. Martello towers, a design adapted by the British from a fortification at Cape Mortella in Corsica, were intended as self-contained defensive posts: compact, hard to assault, and capable of being held by a small garrison. The Skerries example has its southern doorway set above ground level and protected by a machicolation, an opening in the projecting stonework above the entrance through which defenders could drop or pour things onto anyone attempting to force the door. A second doorway was later inserted into the northern face. The tower remained active with the gunners of the Royal Artillery until it was disarmed in 1874, with Archibald Reid serving as Master Gunner from 1848 until that point.

Red Island is accessible from the Skerries shoreline, and the tower stands within a park on the southern side of the island. The machicolation above the southern entrance is worth examining closely, as is the offset course of masonry that marks the transition to the upper portion of the tower. The rectangular window openings in the interior are now blocked. Visitors looking across from the tower's elevated position will find the Shenick Island tower clearly visible, which gives a useful sense of how the chain of coastal defences was laid out along this stretch of the Dublin coastline.