Weaving Shed Museum, Roe Valley Country Park, Dogleap Road, Largy, Limavady, Co Londonderry, BT49 9NN

A former mill building of the early 19th century, sited in the Roe Valley Country Park near Limavady and now operating as a museum. The building is of considerable historical interest for its association with the once important linen industry on the River Roe, though its conversion to museum use has obscured evidence of the original mill wheel and race, and the interior has been entirely renewed.

The structure is a two-storey, nine-bay building constructed in stone with brick trims around the window and door openings. It is roofed in natural slate with a strap concrete coping. The building is well preserved and in good condition, and as architecture it is pleasing and well proportioned.

The south-west elevation contains the main museum entrance, accessed across a bridge at first-floor level to a central semi-circular arch. Above and below this entrance are timber casement windows to four tall openings on each side, each with 12 panes and tall proportions. Below these are similar windows with segmental heads of more normal proportion. The north-east elevation, facing the car park of the Roe Valley Country Park, is blank but displays a large cast-iron water wheel as an exhibit (though there was never a millrace on this side). The north-east elevation overlooks an enclosed maintenance yard and contains seven windows arranged regularly at first-floor level in the same pattern as the south-west elevation. At basement level are two doors with roller shutters interspersed between six smaller segmental-head windows and a door. Above one of these doors is a large window measuring two and a half metres wide at first-floor level; above the other is a segmental hinged door. The south-east elevation is blank, though the former millrace still passes to one side. A timber mill wheel sits near the race, an antique formerly displayed but removed for health and safety reasons.

The millrace is connected to a sluice gate to the south-west of the building, itself fed by a millrace travelling from Sam Moore's Weir 400 metres to the south-east on the River Roe. In front of the building stand a reconstruction of a horse-drawn oats or flax grinder and a scalloped pounding stone. The mill race once extended to the corn mill but was diverted in the last century to increase the head in the mill pond.

The building is indicated on the Ordnance Survey Map of 1830, though not labelled as a mill. It was probably one of the buildings associated with the bleaching of linen on Largy Green to the north-west, which ceased to operate in 1831 according to the Ordnance Survey Memoirs of 1834-5. It may have been among the three houses of the old bleach green occupied for a linen manufactory established in 1833, though it is more likely these were three buildings adjacent to Roe Green to the south. The building is marked as an "Old Beetling Mill" on the 1848 Ordnance Survey Map, a process used to finish linen and give it a shine by repeated impacts of wooden hammers on the cloth. The manufactory prepared yarn to be given out to local weavers, an earlier stage of the process. Its name, "The Weaving Shed", suggests it was later converted to serve as a replacement for the cottage industry of weavers as mechanisation increased during the latter 19th century. The industry was reported derelict in 1857, and the 1848 label confirms the building had already fallen into disuse ten years earlier.

The building is reputed to have been used in the early electrical experiments of John Edward Rritter in the 1880s, and according to the wardens of the Roe Valley Country Park, he was responsible for the unusual style of windows during a renovation in 1901. This claim is not substantiated by the authoritative work "Electricity from the Red River", which names only the saw mill (now demolished) as the site of the electric works. The large-scale 1907 map clearly shows a mill race emerging from the centre of the building, a feature marked on the 1830 map but omitted in 1848. Any use to which the mill was put was probably discontinued to increase the head for electricity generation at Largy Power Station during the early years of the 20th century. By the 1976 Ordnance Survey edition, the building was ruinous and without a roof. It was incorporated into the Roe Valley Country Park in 1976, renovated by the Department of the Environment, and converted into a museum in 1984.