The building's east wall was reconstructed using masonry from an earlier structure, so even its fabric is a palimpsest. More strikingly, excavations at Glanworth Castle uncovered a paved area made from millstones, almost certainly salvaged from the mills along this stretch of river, suggesting that the relationship between the castle and the mills below it was long and practically entangled.

The 1842 Ordnance Survey six-inch map records the site as an L-shaped flour mill, and a second flour mill once stood on the opposite bank to the south of Glanworth Bridge, though nothing of that building remains. By 1837, when the topographer Samuel Lewis was compiling his account of Irish towns and parishes, the mill was listed as the property of Messrs. Murphy and Kelleher. Decades later, the antiquarian Grove White recorded it as a woollen mill belonging to John F. Quinlan and Co., though he noted it had been burned some years before he wrote. Despite the change in trade and the fire, the structure survived. Its water supply came from a weir roughly 150 metres to the north, channelled along a millrace, with the tail race running beneath Glanworth Bridge to the south. The wheel-pit alongside the east wall still holds a cast-iron poncelet waterwheel, a type designed with curved paddles to extract maximum energy from a low head of water, measuring about 4.5 metres in diameter. A carding machine, used to prepare raw wool fibres for spinning, was also retained in the modern buildings to the south, along with bags of wool, giving the site a texture of industry that persisted long after the main building's working life ended. The mill was restored and converted into a restaurant in 1998.