Melin Traethcoch was in existence before 1630, when it was bought by the Bold family. A 1774 survey reported that it was short of water, and that the mill and malting kiln were in want of repair, but nevertheless the mill continued until 1889.
The 1st and 2nd editions of the 25-inch O.S. maps (1889 and 1900) show the mill building separated from the beach only by a narrow track. Its pond to the south is silted up by 1900. Neither are shown on the 3rd edition, and buildings to the north which may have included the mill house and kiln are also reduced. In November 2008 the course of the leat and the sites of the pond and mill were covered in a dense, impenetrable thicket. A few large stones at the head of the beach lie close to the site of the mill.

Other sources include:
Morris, L, 1740, Plans of the Harbours, Bars, Bays and Roads in St Georges Channel, plate 4

W J Crompton, RCAHMW, 19 November 2008.