The northeastern corner still rises to first floor level and contains a wall press, whilst its northwestern counterpart stands as little more than a featureless stump. Between them, a modern dry stone wall connects these lonely sentinels, which once formed part of a much grander fortification that controlled this strategic position overlooking the water.

The castle's history stretches back to the early 13th century when it was known as the Castle of Robert Guher or Gore, appearing in church lists and rentals throughout the medieval period. For centuries it remained in the possession of the powerful Earls of Desmond until their surrender in the late 16th century. The site then passed through various hands; in 1571 J. Mac Clanchy held it, followed by W. Trenchard in 1587, and by 1608 it had been conveyed by James Wakeman to Sir Richard Wingfield of Smithstown, along with a water mill and surrounding lands. The Civil Survey of 1654-56 recorded Sir Edward Wingfield as owner of Robertstown and Garrintober, noting the castle was already ruined by then, though two mill seats remained functional.

Archaeological assessments describe the ruins as fragments of a peel tower, with traces of a strong defensive wall that once stretched across the neck of the peninsula, effectively turning the entire spit into a fortified position. Though much reduced from its medieval glory, these remnants offer a tangible connection to eight centuries of Irish history, from the Anglo-Norman settlement through the tumultuous changes of ownership during the Tudor conquest and beyond.