This remarkably intact medieval complex consists of a tower house and fortified house, built separately in the 15th century with only their adjacent corners touching. The Laffan family, who likely built these structures, had been prominent in the area since at least 1376, when Thomas Laffan of Ross was granted the benefit of English law. By 1541, Nicholas Laffan held 120 acres in Hooke parish from the Knights Hospitallers, and the family continued to maintain their presence through centuries of political upheaval, including the Cromwellian period when many Irish landowners were dispossessed.

The five-storey tower house remains complete to its stepped battlements, standing 15.7 metres high with distinctive battered walls and excellent quoins. Its defensive features include a round-headed doorway on the south wall protected by both external machicolation and an internal murder hole. Inside, the tower contains two barrel vaults; one above the first floor and another above the fourth, with the latter retaining evidence of its original wicker-centring. A mural staircase in the south wall connects the lower levels, whilst a newel stair at the southeast angle spirals upward through the building. Each floor served different purposes, from storage on the ground level to living quarters on the middle floors, complete with fireplaces, garderobe chambers, and window seats. The third floor even features cupboards built into the northeast and southwest corners, showing the medieval attention to domestic comfort alongside military necessity.

The castle’s fortunes shifted through various owners over the centuries. After the Laffans, it passed to Nicholas Loftus in 1666, and by 1684 Henry Loftus had built the old quay at Slade. The following year, William Mansel rented the castle and established saltworks, beginning a new chapter of industrial use. Both the tower house and fortified house, along with additional structures, continued to be inhabited in multiple units well into the 20th century. Today, as National Monument No. 429 under state guardianship, Slade Castle offers visitors an exceptionally well-preserved example of late medieval defensive architecture, its walls still bearing witness to over 500 years of Irish history.