It is, in fact, a windmill tower, and a remarkably complete one at that. Rising to roughly 6.4 metres across three storeys, with an external diameter of 4.7 metres and an interior of 2.8 metres, it retains opposing doorways on its east and west faces, a series of projecting internal steps, and three slit windows on the second floor. A date inscribed on a stone above the eastern doorway reads 174, with the final digit uncertain but possibly a 9, placing its construction somewhere in the mid-eighteenth century. The initials "I" and "ID" are incised into the southern side of the western door frame, though to whom they belong is no longer known.

The Ballyseskin site has a longer milling history than the surviving tower suggests. A mill here was recorded in the ownership of one George Chevers as early as 1640, though whether that earlier mill was wind-powered or otherwise is unclear. By 1839, the Ordnance Survey six-inch map identified the present structure explicitly as a windmill, confirming its function at least by that point. Aerial photography has revealed something else of interest: traces of a circular enclosure roughly 25 metres in diameter surrounding the tower, defined by what appears to be a shallow channel or fosse. One interpretation is that this groove was worn into the ground by the pole used to rotate the cap of the mill, the rotating cap being the mechanism by which the sails were turned to face into the wind. If so, the enclosure is not a boundary feature at all, but a physical record of the mill's working life, etched into the earth by the labour of turning it.