Whilst the exact date of its construction remains lost to history, the castle emerges into the historical record around the mid-16th century, a turbulent period when the Desmond Earls controlled vast swathes of Munster. The fortress would have been a symbol of their authority in Kerry, standing as both a defensive structure and an administrative centre for their local holdings.

Like many Irish castles of the period, it likely featured the typical defensive elements of a tower house; thick stone walls, narrow windows, and a commanding position over the surrounding townscape. The Desmonds themselves were a fascinating blend of Norman heritage and Gaelic culture, often finding themselves at odds with English colonial authority whilst maintaining their own fierce independence. Their castles, including this one in Tralee, formed a network of power bases across the province.

The castle survived through centuries of conflict, rebellion, and changing ownership before meeting its end not through siege or warfare, but through the more mundane forces of urban development. In 1826, after standing for perhaps 400 years or more, the ancient stones were pulled down, making way for Tralee’s modernisation. Today, nothing remains of the Earl’s fortress; Denny Street shows no trace of the medieval power that once loomed over its northern end, leaving only archival mentions and archaeological surveys to hint at what once stood there.