Flax store at, Mary Brook Mills, 11 Raleagh Road, Drummaconagher, Crossgar, Downpatrick, Co. Down, BT30 9JG

Mary Brook Mills is an extensive and largely complete small-scale Georgian vernacular rural milling complex dating from the 18th and early 19th centuries, located at the end of a lane to the west of Raleagh Road, roughly two and a half miles east of Ballynahinch, with the Ballynahinch River immediately to the west and mill pond to the south.

The complex comprises water-powered two-storey corn and flax mills and a single-storey stable block, all probably dating from the mid to late 1700s; a two-storey miller's house built in 1837; and subsidiary structures including a small cottage and storehouse dating from around the 1840s. To the rear of the house are large two and single-storey wings, a section of which appears originally to have been a barn.

The whole grouping presents a uniform appearance with harled and whitewashed facades, slated roofs, and Georgian paned sash windows and timber sheeted doors. This is complemented by the abundance of traditional wrought iron farm gates, stone walling, and simple gate pillars.

The flax store stands to the north of the flax mill and is a large single-storey gabled building with harled and whitewashed facade and slated roof. It features a relatively large flat arch doorway without door to the east gable, and a high-level window opening without frame to the west gable. The long north and south facades are blank. The building appears to be a simple and partly rebuilt structure that, whilst complementary to the setting of the site, is not considered to be of special architectural or historical interest as an individual building.

The complex is recorded on the Ordnance Survey map of 1834 and in the valuation returns of 1836. The corn mill, flax mill, and stable all appear on these records. The present two-storey dwelling was built in 1837, possibly incorporating fabric from an earlier single-storey dwelling that had occupied the site and was believed by valuers to date from the early to mid 1700s. The barn to the south of the house and the storehouse to the north of the flax mill were also added around 1837 and appear on the revised Ordnance Survey map of 1858.

The 1861 valuation records the house and mill in the possession of Christiana Silcock, who leased them from Alexander John and Robert Stewart Esq. At its height in the late 19th century, the Mary Brook complex employed around 150 people, not only in corn and flax milling but also in a small hemstitching factory situated in a now-modernised building along the main drive off Raleagh Road. The hemstitching factory closed around 1900, with the flax mill ceasing production a few years later. The corn mill continued in full-time use until after the First World War, with production halting by the 1930s.

The grouping was abandoned in the 1950s and lay largely derelict until the early 1970s, when it was acquired by Mr Lewis-Crosby, a senior figure within the National Trust, who restored the buildings and brought the corn mill back into operation. The present owner acquired the complex in 1998. At the time of the record (October 2000) the corn mill was not in use.