The castle was likely constructed by Hugh de Lacy between 1182 and 1187, though it sits atop an even older fortress known as Rath Guaire. By 1211–12, historical records show the castle had passed to Robert de Lacy, as noted in the Irish Pipe Roll of that year.

Today, visitors can explore a large, steep-sided mound with a flat top, accompanied by a kidney-shaped bailey to the south. These two features are separated by a fosse, or defensive ditch, which contains fragments of masonry from a stone castle that may date to the early 13th century. Whilst no foundations of this stone structure remain visible, it likely stood within the bailey, which was originally enclosed by an earthen bank and external fosse. The modern public road now cuts through the eastern side of the bailey, obscuring any trace of the original enclosing elements in that area.

The site reveals intriguing archaeological puzzles; a linear earthwork stretching approximately 143 metres north of the motte might represent either part of the stone castle's enclosing defences or remnants of a pre-Norman enclosure. The curving earthwork of the bailey itself, bisected by the modern road, could alternatively be the remains of an earlier Irish fortification, with the northern earthworks representing the medieval bailey. South of the motte, various earthworks appear to be the remains of a post-1700 field system, complete with quarry holes and a possible trackway leading towards the bailey. The Ordnance Survey 25-inch map also records a post-1700 limekiln situated just southwest of the bailey's fosse, likely connected to these later industrial activities.