What remains today is modest yet intriguing; a portion of a stair tower built from mortared ashlar limestone blocks, rising two storeys with a partially vaulted ground floor. This surviving structure appears to be part of what was once a gatehouse, as depicted in a 1773 drawing by the artist Beranger. The tower represents just a fragment of what was once a much grander fortification.

In its heyday, Deansrath Castle was an impressive defensive complex. The eighteenth-century antiquarian Austin Cooper documented that the castle was surrounded by a deep fosse, a defensive ditch that would have made any unwelcome approach considerably more challenging. The property belonged to the Dean of St. Patrick's Cathedral in 1641, reflecting the significant ecclesiastical landholdings typical of the period. However, the castle's fortunes declined rapidly; by 1656, merely fifteen years later, historical records rather poignantly describe it as nothing more than 'the stumpe of a castle'.

Today, visitors to this unassuming site might easily pass by without realising they're looking at the bones of a once formidable stronghold. The surviving stonework, though weathered, still displays the careful craftsmanship of medieval builders, whilst the partially vaulted chamber hints at the architectural ambitions of its creators. It serves as a compelling reminder of how even the mightiest structures can be reduced to fragments, their stories preserved only through scattered historical accounts and the dedication of local historians.