The site takes its name from Ruby O'Connor, its traditional owner, and remained in O'Connor Roe hands well into the 1600s. During the tumultuous period of 1641, the land belonged to Hugh Morgagh Ó Connor Dunn, but the Cromwellian conquest and subsequent Act of Settlement between 1662 and 1684 saw the property transferred to Ellen and George Talbot, the Earl and Countess of Fingal. Their daughter Mary would later marry into the Plunkett family of nearby Castleplunket, further intertwining the noble families of the region.

What remains today is a rectangular stone foundation measuring approximately 15 metres north to south and 7.3 metres east to west, defined by grass-covered stone spreads that rise only 20 centimetres high but stretch 2 to 3 metres wide. Archaeological evidence suggests this may be the remnants of a house built by the Talbots atop an earlier O'Connor castle, a common practice during the plantation period when new landowners sought to establish their authority whilst making use of existing fortifications.

The castle ruins form the centrepiece of a 1.5-hectare area that still bears traces of its agricultural past. Three small rectangular fields, each roughly 40 by 30 metres, are outlined by low earthen banks and scarps, offering visitors a glimpse into the modest scale of rural Irish estate management during the early modern period. These field boundaries speak to the dual purpose of such sites; not just defensive strongholds, but working farms that sustained both the landed gentry and their tenants through centuries of political upheaval.