Castle - motte and bailey, Castleknock, Co. Dublin
Standing on a steep natural rise west of the Vincentian College in Castleknock, this impressive motte and bailey castle occupies one of the highest points in the local landscape alongside Windmill Hill.
Castle - motte and bailey, Castleknock, Co. Dublin
The motte itself is an oval-shaped earthwork measuring approximately 30 metres from northeast to southwest and 25 metres from northwest to southeast, rising to a height of 18.5 metres. At its eastern end, you’ll find the remains of a keep and castle, whilst a curtain wall runs from north to east where the ground falls away sharply. The southern boundary is marked by a tree line, beyond which lies another steep drop. Within this enclosed area sits the Priest’s graveyard, adding another layer of historical significance to the site.
The defensive earthworks consist of two fosses, or ditches, that encircle the motte. According to observations made by Ball in 1920, these features were considerably better preserved a century ago. Today, the upper fosse remains visible only along the northwestern side, measuring about 5 metres wide and 3 metres deep, though it has silted up towards the east-southeast where a pathway leads up to the keep. The lower fosse, roughly 10 metres wide and 4.5 metres deep, forms a more substantial barrier with an outer hedge running along its exterior edge.
What’s particularly interesting about these fosses is their flat-bottomed design, which remains relatively clear; this may indicate they served a dual purpose as defensive ditches and access pathways. The site offers extensive views across the surrounding countryside, a strategic advantage that would have been invaluable to its medieval builders. Though time has taken its toll on the structure, the earthworks and stone remains still convey the imposing presence this fortification once commanded over the Dublin landscape.