It measures roughly thirteen metres across at its longest and rises no more than a metre or so above the surrounding terrain. Thorn bushes have colonised its surface, which gives it a slightly unkempt, bounded look, but there is nothing about it that announces itself as ancient or significant. That unassuming quality is part of what makes it worth knowing about.

The site appears on the 1843 Ordnance Survey six-inch map, where it is recorded as a large oval enclosure, suggesting that at mid-nineteenth century it was still legible enough to be noted and named. By 1876, however, a source cited by Handcock in his work on Dublin antiquities recorded that the feature, referred to there as a moat, had nearly disappeared. The word moat in this context almost certainly refers not to a water-filled ditch but to a motte, the raised earthen mound that formed the core of an early Anglo-Norman fortification, a type of defensive structure introduced to Ireland after the twelfth-century invasion. Mottes were typically topped with a timber tower and surrounded by an enclosed yard called a bailey. Whether Killinardan once carried such a structure is not recorded in the available sources, but the oval form and the prominence given to it on the OS map suggest it was once a more substantial earthwork than what survives today.

The mound sits on steeply sloping, uneven ground at the foot of the Dublin Mountains, which makes the approach slightly awkward underfoot. There are no visitor facilities and nothing marks the site for a general audience, so locating it requires some preparation. The 1843 OS six-inch map, freely available through the OSi historical mapping portal, is the most useful reference for getting your bearings. Once there, the thorn-covered rise is the thing to look for, modest in scale but persistent, having outlasted the observations of those who noted its decline nearly a hundred and fifty years ago.