The first two editions of the 25-inch OS maps name this site 'Melin Llywenan', indicating that the site was originally a corn mill. The 3rd edition shows the building extended to the south-east, and re-named 'Llywenan Factory'. Water was taken from Llyn Llywenan to a pond immediately east of the mill, and the tail race fed Pandy Llywenan (NPRN 40821) 300 metres to the south-west.

The corn mill probably dates from the late eighteenth or early nineteenth century, and its two storeys are built of random rubblestone under a pitched slate roof. The wheelpit is on the north gable; by 1975 the wheel had been removed but its heavy wooden axle and a massive wooden launder remained in situ. The single storey extension, built of heavily mortared rubble with a slate roof, was probably added at the beginning of the twentieth century when the corn mill was acquired by the owner of Pandy Llywenan and converted to wool spinning with a third-hand spinning mule. Weaving, fulling and dyeing continued at Pandy LLywenan, producing heavy woollen cloth for local use. However, in 1940 both buildings were acquired by a new owner and began making fashion tweeds. It was the last woollen mill to operate in Anglesey. In 1975 the faded name "Anglesey Tweed Mill" could still be discerned on the door to the extension. Inside the building, under stored hay, were a carding engine by Cliffe and Co, Longwood near Huddersfield, and several other items of textile machinery.

Information from Cadw Listed Buildings database
W J Crompton, RCAHMW, 15 May 2014.